**6. High risk and elderly patients, are they the same?**

#### **6.1. Elderly patient**

net scale reveals that this scale assigns too much weight to age. Nowadays the STS score and logistic EuroSCORE are the most commonly used. These provide information concerning short term operative risks, however, they are not able to predict symptom resolution, quali‐

As discussed above (see also Evaluation and Grading the Degree of Stenosis), several stud‐ ies have reported the usefulness of BNP in risk stratification of asymptomatic or mildly symptomatic patients, which could help to discriminate which patients would benefit from an early surgical management. However, there is not enough evidence to recommend the

Although both are accurate in low-risk patients, accuracy is reduced in higher-risk subsets [15]. The logistic EuroSCORE is based on 12 covariates derived from 14,799 patients under‐ going all types of cardiac operations in 8 European countries in 1995. On the other hand, the STS risk predictor is based on 24 covariates derived from 67,292 patients undergoing isolat‐ ed AVR only in the United States between 2002 and 2006. Both use an algorithm based on the presence of coexisting illnesses in order to estimate 30-day operative mortality. There is a much simpler variation of the EuroSCORE logistic model, which can be calculated at the patient's bedside, adding points manually. This model is called the additive EuroSCORE. It assigns a specific value to each risk factor, and the points are simply added to obtain the es‐

With improved outcomes after cardiac surgery in more recent years, EuroSCORE has be‐ come less well calibrated. EuroSCORE II has been developed using data from 22.381 pa‐ tients who underwent cardiac surgery during 2010, and represents a necessary and timely update of the original EuroSCORE models. EuroSCORE II improves on the original logistic EuroSCORE, though mainly for combined AVR and CABG cases. However, concerns still exist, about its use for isolated AVR procedures, aortic surgery and miscellaneous proce‐ dures. There is still room for improvement in risk modelling and several studies are current‐ ly being carried out to validate EuroScore II. Nevertheless, Grant et al [16] report that EuroSCORE II performs well overall in contemporary UK adult cardiac surgery, with good discrimination for all kinds of cardiac surgery; in fact, they report that the logistic Euro‐ SCORE is now obsolete and their study demonstrates that it is appropriate to use Euro‐

There is growing debate about the definition of high-risk patients and the validity of risk as‐ sessment using different risk-scoring systems for prediction of mortality (see also **High-Risk Patient**). Current models do not include some risk factors that may be particularly important in the prediction of outcomes for high- or very high-risk populations including frailty, pulmonary hypertension (PH), porcelain aorta, and the presence of hepatic dysfunc‐

Nevertheless, the sample of elderly patients considered for the design of these scales repre‐ sents a small proportion of the population, resulting in less accurate risk assessment, and in‐ terpretation should be made with caution. In this regard, a recent study which included 1245 elderly patients (mean age 77.2 years) who underwent AVR with or without CABG re‐

SCORE II as a generic risk model for contemporary UK cardiac surgery.

tion, although all these have been included in EuroSCORE II.

ty-of-life improvement, or return to independent living.

routine use of these biomarkers.

456 Calcific Aortic Valve Disease

timated operative mortality rate.

The ageing of the population is an important social and sanitary phenomenon. Consensus about allowing access to health care unconstrained by age limits, together with increased life expectancy and advances in highly specialised medicine have brought us to the point where surgical treatment is indicated in progressively older sectors of the population [21]. The di‐ agnosis and management of valvular heart disease in the elderly has been affected by the dramatic increase in life expectancy that began in the last half of the 20th century. In the United States, for example, the number of persons aged 80 years or older is expected to in‐ crease from 6.9 million in 1990 to approximately 25 million by the year 2050. As a result, de‐ generative valve disease is likely to become an increasing problem. In the Helsinki Ageing Study [22], 501 randomly selected men and women aged 75 to 86 underwent imaging and Doppler echocardiography. The prevalence of at least moderate aortic stenosis, defined as an aortic valve area (AVA) ≤1.2 cm<sup>2</sup> and velocity ratio ≤0.35, was 5 percent; the prevalence of critical aortic stenosis (AVA ≤0.8 cm<sup>2</sup> , and velocity ratio ≤0.35) increased with age from 1 to 2 percent in persons aged 75 to 76 up to almost 6 percent in those aged 86. With the rapidly increasing geriatric population, it is common in current practice to have elderly patients re‐ ferred for surgical treatment of AS. In 2006, in the United States, approximately 40% of pa‐ tients undergoing AVR were at least 75 years old Nevertheless, even though valve replacement is the procedure of choice in this population, currently a large percentage of suitable candidates are, unfortunately, not referred for surgery, mostly because of their age.

lished the outcomes of the very elderly undergoing aortic valve surgery in a study comprising 7584 patients, including 815 over the age of 80. They found that short- and longterm survival was favourable across all age groups. Specifically, more than half of the pa‐ tients undergoing aortic valve procedures were alive 6 years after surgery. Among patients under 80 years of age, survival favoured those undergoing isolated AVR procedures, but among octogenarians, concomitant CABG surgery did not result in reduced survival. Ya‐ mane K et al [26] published the outcome of a single-centre study of conventional AVR in pa‐ tients aged 70 or older. In their analysis, patients aged 80–92 who underwent isolated AVR or AVR with CABG showed an acceptable mortality rate of 4.0%, comparable to the 3.8% mortality rate in patients aged 70–79. Brown et al [27] published the outcomes of isolated AVR in North America by analysing the STS National Database, comprising 108,687 pa‐ tients, and compared the mortality rates in 1997 with those in 2006. In their analysis, patients aged 70–75 had a mortality rate of 3.2% in 1997 and 2.9% in 2006; for patients aged 80–85, the mortality rate was 6.3% in 1997 and 4.9% in 2006. These improvements in operative out‐ come over the past decade could be related to multiple factors, including patient selection and perioperative management. A better understanding of the role of preoperative respira‐ tory preparation, improved myocardial protection of otherwise severely hypertrophic myo‐ cardium, as well as normothermic cardiopulmonary bypass may have contributed to the improved early postoperative results in recent studies as compared to those several decades ago. Yamane K et al [26] propose that with the elderly, especially those aged 80 years or old‐ er, goal-oriented strategies such as early extubation, judicious sedation management, medi‐ cation dosage based on renal or liver function, early involvement of physical or occupational

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459

From a patient's perspective, functionality after surgery may be more important than simple survival. Using the Seattle Angina Questionnaire, Huber et al [28] interviewed 136 patients who were 80 years of age at the time of cardiac surgery (isolated CABG, AVR, or AVR +CABG). They found that 95% lived in their own homes, and 93% reported that they had experienced no reduction in their quality of life. Kolh et al [29] interviewed 61 long-term survivors of AVR and found that 92% of patients believed that having heart surgery at age 80 was a "good choice," with 88% of patients feeling "as good or better" than they had be‐ fore surgery. Also, Maillet et al [30] reported results from 84 octogenarians undergoing ei‐ ther AVR or AVR+CABG between 1998 and 2001. The majority (91.1%) lived in their own homes (compared with 75% of the general French population aged 80 years), whereas 26.7% of patients required help with activities of daily living (compared with 35% to 40% of the general population). Sundt et al [31] reported functional status and survivorship up to 5 years among 133 patients undergoing AVR with or without CABG. Patient-reported func‐

Because there is no effective medical therapy and balloon valvotomy is not an acceptable al‐ ternative to surgery, AVR is the gold standard for the treatment of severe stenosis and must be considered in all elderly patients who have symptoms caused by AS [10]. Age, per se, should not be considered a contraindication for surgery. Decisions should be made on an individual basis, taking into account patients' wishes and cardiac and non-cardiac factors

therapists, and speech/swallow specialists are all indispensable.

tional status was comparable to the general population.

As in [21], increased risk in these patients is related to:


Age has been considered an independent predictive factor for mortality, but the way to esti‐ mate its influence on the calculation of the risk of surgery has evolved since the introduction of the Parsonnet risk scale, which gave excessive weight to age. Currently the most accepted risk assessment tools are the STS-PROM score and EuroSCORE (with the EuroSCORE II cur‐ rently being validated).Although they are widely used, there is a possibility of overestimat‐ ing the operative mortality rates by using these risk-prediction models, and an inescapable discrepancy between the estimated and observed mortality rate has been acknowledged. In a study published in Ann Thorac Surg in 2009 Thielmann et al [18] report that the logistic EuroSCORE clearly overestimates the risk of mortality, whereas the STS score seems to be more accurate in predicting the risk of mortality. Moat et al. [24] also report the relative lack of utility of EuroSCORE in risk/outcome prediction for their group of patients and confirm the need for more sophisticated and procedure-specific (rather than generic) scoring sys‐ tems. There is no perfect method for weighing all of the relevant factors and identifying spe‐ cifically high- and low-risk elderly patients, but this risk can be estimated well in individual patients, and the decision to proceed with surgery should depend on many factors, includ‐ ing the patient's wishes and expectations.

Although the proportion of elderly patients with multiple comorbidities is increasing, oper‐ ative outcomes following AVR have improved over the past decade. Likosky et al [25] pub‐ lished the outcomes of the very elderly undergoing aortic valve surgery in a study comprising 7584 patients, including 815 over the age of 80. They found that short- and longterm survival was favourable across all age groups. Specifically, more than half of the pa‐ tients undergoing aortic valve procedures were alive 6 years after surgery. Among patients under 80 years of age, survival favoured those undergoing isolated AVR procedures, but among octogenarians, concomitant CABG surgery did not result in reduced survival. Ya‐ mane K et al [26] published the outcome of a single-centre study of conventional AVR in pa‐ tients aged 70 or older. In their analysis, patients aged 80–92 who underwent isolated AVR or AVR with CABG showed an acceptable mortality rate of 4.0%, comparable to the 3.8% mortality rate in patients aged 70–79. Brown et al [27] published the outcomes of isolated AVR in North America by analysing the STS National Database, comprising 108,687 pa‐ tients, and compared the mortality rates in 1997 with those in 2006. In their analysis, patients aged 70–75 had a mortality rate of 3.2% in 1997 and 2.9% in 2006; for patients aged 80–85, the mortality rate was 6.3% in 1997 and 4.9% in 2006. These improvements in operative out‐ come over the past decade could be related to multiple factors, including patient selection and perioperative management. A better understanding of the role of preoperative respira‐ tory preparation, improved myocardial protection of otherwise severely hypertrophic myo‐ cardium, as well as normothermic cardiopulmonary bypass may have contributed to the improved early postoperative results in recent studies as compared to those several decades ago. Yamane K et al [26] propose that with the elderly, especially those aged 80 years or old‐ er, goal-oriented strategies such as early extubation, judicious sedation management, medi‐ cation dosage based on renal or liver function, early involvement of physical or occupational therapists, and speech/swallow specialists are all indispensable.

percent in persons aged 75 to 76 up to almost 6 percent in those aged 86. With the rapidly increasing geriatric population, it is common in current practice to have elderly patients re‐ ferred for surgical treatment of AS. In 2006, in the United States, approximately 40% of pa‐ tients undergoing AVR were at least 75 years old Nevertheless, even though valve replacement is the procedure of choice in this population, currently a large percentage of suitable candidates are, unfortunately, not referred for surgery, mostly because of their age.

**•** Ageing, which causes structural changes in the heart and reduces the physiological re‐ serves of most organs, thus impairing the capacity to recover from surgical aggression; **•** An increase in associated diseases, as studied by Rodríguez et al [23], especially diabetes, kidney failure, arterial hypertension, chronic obstructive pulmonary disease, and cerebro‐

**•** The advanced phase of heart disease, as indicated by the greater incidence of heart fail‐ ure, depressed left ventricular function, and preoperative pulmonary hypertension;

**•** Undernourishment, measured by anthropometric and biochemical parameters, which is a frequent preoperative finding before cardiac surgery; its incidence is even greater in older persons and is associated with an increment in postoperative complications due to an im‐

**•** The increased complexity of surgical techniques for these patients, due to the presence of severe calcification of the aortic ring and the greater incidence of associated coronary and

Age has been considered an independent predictive factor for mortality, but the way to esti‐ mate its influence on the calculation of the risk of surgery has evolved since the introduction of the Parsonnet risk scale, which gave excessive weight to age. Currently the most accepted risk assessment tools are the STS-PROM score and EuroSCORE (with the EuroSCORE II cur‐ rently being validated).Although they are widely used, there is a possibility of overestimat‐ ing the operative mortality rates by using these risk-prediction models, and an inescapable discrepancy between the estimated and observed mortality rate has been acknowledged. In a study published in Ann Thorac Surg in 2009 Thielmann et al [18] report that the logistic EuroSCORE clearly overestimates the risk of mortality, whereas the STS score seems to be more accurate in predicting the risk of mortality. Moat et al. [24] also report the relative lack of utility of EuroSCORE in risk/outcome prediction for their group of patients and confirm the need for more sophisticated and procedure-specific (rather than generic) scoring sys‐ tems. There is no perfect method for weighing all of the relevant factors and identifying spe‐ cifically high- and low-risk elderly patients, but this risk can be estimated well in individual patients, and the decision to proceed with surgery should depend on many factors, includ‐

Although the proportion of elderly patients with multiple comorbidities is increasing, oper‐ ative outcomes following AVR have improved over the past decade. Likosky et al [25] pub‐

As in [21], increased risk in these patients is related to:

**•** Reduction of the inflammatory response to surgical aggression,

valvular surgery, which require longer aortic clamping times.

paired response to surgical aggression.

ing the patient's wishes and expectations.

vascular disease;

458 Calcific Aortic Valve Disease

From a patient's perspective, functionality after surgery may be more important than simple survival. Using the Seattle Angina Questionnaire, Huber et al [28] interviewed 136 patients who were 80 years of age at the time of cardiac surgery (isolated CABG, AVR, or AVR +CABG). They found that 95% lived in their own homes, and 93% reported that they had experienced no reduction in their quality of life. Kolh et al [29] interviewed 61 long-term survivors of AVR and found that 92% of patients believed that having heart surgery at age 80 was a "good choice," with 88% of patients feeling "as good or better" than they had be‐ fore surgery. Also, Maillet et al [30] reported results from 84 octogenarians undergoing ei‐ ther AVR or AVR+CABG between 1998 and 2001. The majority (91.1%) lived in their own homes (compared with 75% of the general French population aged 80 years), whereas 26.7% of patients required help with activities of daily living (compared with 35% to 40% of the general population). Sundt et al [31] reported functional status and survivorship up to 5 years among 133 patients undergoing AVR with or without CABG. Patient-reported func‐ tional status was comparable to the general population.

Because there is no effective medical therapy and balloon valvotomy is not an acceptable al‐ ternative to surgery, AVR is the gold standard for the treatment of severe stenosis and must be considered in all elderly patients who have symptoms caused by AS [10]. Age, per se, should not be considered a contraindication for surgery. Decisions should be made on an individual basis, taking into account patients' wishes and cardiac and non-cardiac factors [12]. In this population, the need for an emergency operation, or, at the other end of the clin‐ ical spectrum, very early intervention at an asymptomatic stage, should be avoided.

tional AVR. Nevertheless, several previous reports on TAVI defined high-risk patients as patients with a logistic EuroSCORE between 10% and 30% [18]. Smith et al [34] in a TAVI versus AVR paper published in the New England Journal of Medicine in 2011 used as a guideline a score of at least 10% on the risk model developed by the STS to define high-risk patients. However, there are multiple additional risk factors, which are not currently consid‐ ered by existing risk scoring systems; for example the presence of a porcelain aorta and con‐ siderations such as social integration, mobility, frailty, and the individual's overall health status must be taken into account, as well as the patient's wishes and expectations. A further definition that must be taken into account for evaluation of those patients who underwent TAVI is that very or extremely high-risk patients are those with a logistic EuroSCORE above 30% or STS score higher than 15% (see Table 2). The 2012 ACCF/AATS/SCAI/STS Expert Consensus Document on Transcatheter Aortic Valve Replacement [15] used the term *prohibi‐ tive risk*. This includes some patients for whom surgery might be deemed unsuitable based on the physician's assessment of the patient's risk for surgery; whereas in others, the sur‐ geon may decide that the operation cannot be performed successfully because of technical

New Therapeutic Approaches to Conventional Surgery for Aortic Stenosis in High-Risk Patients

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461

*High risk* 10-30% "/>10% *Very or extremely high risk* "/>30% "/>15%

Based on the 2012 ACCF/AATS/SCAI/STS Expert Consensus Document on Transcatheter Aortic Valve Replacement

In the absence of evidence in the literature and recommended guidelines, the determination of inoperability in any given patient depends on the judgement of the Heart team. It is gen‐ erally agreed that patients with limited life expectancy due to concurrent conditions such as malignant tumours, dementia, primary liver disease or COPD, among others, are not appro‐ priate for AVR. Frailty and poor physical condition are known to result in an inability to re‐ cover from major heart surgery such as AVR. These conditions can potentially contribute to increased surgical mortality and morbidity in the elderly. The surgeon may judge a patient inoperable as a result of technical considerations that preclude safe performance of AVR, such as prior mediastinal irradiation, porcelain aorta or severe periannular calcification, se‐ vere atheromatous disease, prior cardiac operations, and other conditions such as the inter‐ nal mammary artery crossing the midline. In summary, a substantial percentage of patients with AS are judged to be inoperable for surgery based primarily on the physician's or sur‐ geon's determination of operative risk and probability of survival [15]. Although some pa‐ tients may be found to be inoperable for technical and surgical reasons, most inoperable patients are considered to be too ill due to associated comorbid conditions. In conclusion,

**Risk assessment tool**

**EuroSCORE STS score**

considerations.

**Table 2.** Risk Assessment

[15].

The surgical community worked vigorously over the past two decades to reduce the trauma of the conventional aortic valve operation. Ongoing studies of transcatheter aortic valve im‐ plantation (TAVI) have demonstrated feasible short- and mid-term results in patients who were not considered suitable candidates for conventional AVR. Minimally invasive ap‐ proaches like partial upper sternotomy have replaced the conventional complete median sternotomy when performing AVR in many centres. By aiming for smaller incisions, with‐ out compromising the quality of the operation and the effectiveness of myocardial protec‐ tion, improved early outcomes have been achieved.

In a prospective randomised trial, Dogan et al [32] show that minimally invasive AVR can be performed with only slightly longer operative times, good cosmetic results and improved rib cage stability as well as significantly less blood loss. Furthermore, limited surgical access had no negative effects on the patients' neurological outcome nor the efficacy of myocardial protection. More recently, the implantation technique for AVR has also been modified, with‐ out compromising the hemodynamic performance of the valve substitute, all in order to re‐ duce implantation times, and therefore reduce ischemia in the myocardium and cardiopulmonary bypass times. In 2009 Martens et al [33] reported on initial clinical experi‐ ences with the sutureless, nitinol-stented Enable (Medtronic Inc., Minnesota, USA) aortic valve prosthesis in 32 patients. Implantation time could be significantly reduced, down to 9±5 minutes, the first report of multi-centre experience with this particular valve substitute and implantation technique in 140 patients was published in the European Journal of Cardi‐ othoracic Surgery in 2011. Reproducibility as well as feasibility and safety were demonstrat‐ ed with the ATS 3f Enable® Bioprosthesis. Valve implantation resulted in excellent hemodynamics and significant clinical improvement. Further comparative studies are under way to prove the clinical benefit using this less-time-consuming implantation technique ver‐ sus the conventional one.

#### **6.2. High risk patient**

How could we define a cardiac high-risk patient? Which parameters must we consider in order to assess risk? Which is the most accurate assessment tool to calculate a patient's risk?

We could define high risk cardiac patients as those who present several factors that signifi‐ cantly affect their outcome after surgery and could compromise their survival. Multiple ser‐ ies have documented that patients were deemed to have a high risk of operative complications or death on the basis of coexisting conditions such as advanced age, diabetes mellitus, existence of preoperative shock, LVEF ≤40%(≤30%), preoperative NYHA class III or IV, concomitant CAD, concomitant surgical procedure (CABG, valve surgery or surgery on thoracic aorta), renal failure and chronic obstructive pulmonary disease (COPD). Although attempts have been made to identify the high-risk population for AVR, there is currently no ideal model for precisely identifying high-risk patients. STS-PROM score and the European System for Cardiac Operative Risk Evaluation (EuroSCORE) have been used as part of the inclusion/exclusion criteria for the TAVI trials and to quantify the operative risk of conven‐ tional AVR. Nevertheless, several previous reports on TAVI defined high-risk patients as patients with a logistic EuroSCORE between 10% and 30% [18]. Smith et al [34] in a TAVI versus AVR paper published in the New England Journal of Medicine in 2011 used as a guideline a score of at least 10% on the risk model developed by the STS to define high-risk patients. However, there are multiple additional risk factors, which are not currently consid‐ ered by existing risk scoring systems; for example the presence of a porcelain aorta and con‐ siderations such as social integration, mobility, frailty, and the individual's overall health status must be taken into account, as well as the patient's wishes and expectations. A further definition that must be taken into account for evaluation of those patients who underwent TAVI is that very or extremely high-risk patients are those with a logistic EuroSCORE above 30% or STS score higher than 15% (see Table 2). The 2012 ACCF/AATS/SCAI/STS Expert Consensus Document on Transcatheter Aortic Valve Replacement [15] used the term *prohibi‐ tive risk*. This includes some patients for whom surgery might be deemed unsuitable based on the physician's assessment of the patient's risk for surgery; whereas in others, the sur‐ geon may decide that the operation cannot be performed successfully because of technical considerations.


Based on the 2012 ACCF/AATS/SCAI/STS Expert Consensus Document on Transcatheter Aortic Valve Replacement [15].

#### **Table 2.** Risk Assessment

[12]. In this population, the need for an emergency operation, or, at the other end of the clin‐

The surgical community worked vigorously over the past two decades to reduce the trauma of the conventional aortic valve operation. Ongoing studies of transcatheter aortic valve im‐ plantation (TAVI) have demonstrated feasible short- and mid-term results in patients who were not considered suitable candidates for conventional AVR. Minimally invasive ap‐ proaches like partial upper sternotomy have replaced the conventional complete median sternotomy when performing AVR in many centres. By aiming for smaller incisions, with‐ out compromising the quality of the operation and the effectiveness of myocardial protec‐

In a prospective randomised trial, Dogan et al [32] show that minimally invasive AVR can be performed with only slightly longer operative times, good cosmetic results and improved rib cage stability as well as significantly less blood loss. Furthermore, limited surgical access had no negative effects on the patients' neurological outcome nor the efficacy of myocardial protection. More recently, the implantation technique for AVR has also been modified, with‐ out compromising the hemodynamic performance of the valve substitute, all in order to re‐ duce implantation times, and therefore reduce ischemia in the myocardium and cardiopulmonary bypass times. In 2009 Martens et al [33] reported on initial clinical experi‐ ences with the sutureless, nitinol-stented Enable (Medtronic Inc., Minnesota, USA) aortic valve prosthesis in 32 patients. Implantation time could be significantly reduced, down to 9±5 minutes, the first report of multi-centre experience with this particular valve substitute and implantation technique in 140 patients was published in the European Journal of Cardi‐ othoracic Surgery in 2011. Reproducibility as well as feasibility and safety were demonstrat‐ ed with the ATS 3f Enable® Bioprosthesis. Valve implantation resulted in excellent hemodynamics and significant clinical improvement. Further comparative studies are under way to prove the clinical benefit using this less-time-consuming implantation technique ver‐

How could we define a cardiac high-risk patient? Which parameters must we consider in order to assess risk? Which is the most accurate assessment tool to calculate a patient's risk? We could define high risk cardiac patients as those who present several factors that signifi‐ cantly affect their outcome after surgery and could compromise their survival. Multiple ser‐ ies have documented that patients were deemed to have a high risk of operative complications or death on the basis of coexisting conditions such as advanced age, diabetes mellitus, existence of preoperative shock, LVEF ≤40%(≤30%), preoperative NYHA class III or IV, concomitant CAD, concomitant surgical procedure (CABG, valve surgery or surgery on thoracic aorta), renal failure and chronic obstructive pulmonary disease (COPD). Although attempts have been made to identify the high-risk population for AVR, there is currently no ideal model for precisely identifying high-risk patients. STS-PROM score and the European System for Cardiac Operative Risk Evaluation (EuroSCORE) have been used as part of the inclusion/exclusion criteria for the TAVI trials and to quantify the operative risk of conven‐

ical spectrum, very early intervention at an asymptomatic stage, should be avoided.

tion, improved early outcomes have been achieved.

sus the conventional one.

**6.2. High risk patient**

460 Calcific Aortic Valve Disease

In the absence of evidence in the literature and recommended guidelines, the determination of inoperability in any given patient depends on the judgement of the Heart team. It is gen‐ erally agreed that patients with limited life expectancy due to concurrent conditions such as malignant tumours, dementia, primary liver disease or COPD, among others, are not appro‐ priate for AVR. Frailty and poor physical condition are known to result in an inability to re‐ cover from major heart surgery such as AVR. These conditions can potentially contribute to increased surgical mortality and morbidity in the elderly. The surgeon may judge a patient inoperable as a result of technical considerations that preclude safe performance of AVR, such as prior mediastinal irradiation, porcelain aorta or severe periannular calcification, se‐ vere atheromatous disease, prior cardiac operations, and other conditions such as the inter‐ nal mammary artery crossing the midline. In summary, a substantial percentage of patients with AS are judged to be inoperable for surgery based primarily on the physician's or sur‐ geon's determination of operative risk and probability of survival [15]. Although some pa‐ tients may be found to be inoperable for technical and surgical reasons, most inoperable patients are considered to be too ill due to associated comorbid conditions. In conclusion, the decision to proceed with AVR or TAVI requires careful weighing of the potential for im‐ proved symptoms and survival and the morbidity and mortality of surgery.

annulus. The leaflets of the aortic valve are excised to the level of the annulus and the annu‐ lus is thoroughly debrided of any calcium. Braided 2-0 sutures with pledgets are applied. Beginning at the non-coronary commissure, the annulus is encircled with interrupted mat‐

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Next, each half of the suture bundles are implanted in the sewing ring and the prosthesis seated. The sutures are tied first at the left coronary cusp extending to the mid-portion of the right coronary cusp. Lastly, the sutures of the non-coronary cusp are secured, seating the valve appropriately. In case of mechanical valve prosthesis leaflet motion should always be checked and the surgeon must be assured that the coronary arteries are not obstructed. The aortotomy is closed with a double layer of polypropylene suture consisting of an underlying

Regardless of surgical approach, elected AVR is the gold standard for the treatment of se‐ vere AS. Several studies have shown acceptable short- and long-term outcomes, as well as improved quality of life in elderly patients. Although the proportion of elderly patients with multiple comorbidities is expanding, operative outcomes following AVR were still improv‐ ing in the past decade. Recent series such as Likosky et al [25], report 30-day mortality among patients who underwent isolated AVR of 3.7% for patients <80, 6.7% in the 80 to 84 age group, and 11.7% in those ages >85 (P<0.001). Among patients undergoing AVR+CABG, 6.2% of patients <80 years died within 30 days, 9.4% among those 80 to 84, and 8.5% of pa‐ tients ≥85 years (P=0.01). Also M. Di Eusanio et al [37] published a multi-centre study in‐ cluding 638 octogenarians who underwent AVR from an Italian regional cardiac surgery

tress sutures (Figure 4) extending from the ventricular to the aortic surface.

**Figure 4.** Aortic annulus encircled with interrupted mattress sutures

mattress suture and a more superficial over-and-over suture.

*7.1.1. Conventional AVR results*
