**1. Introduction**

106 Special Topics in Cardiac Surgery

Sivakumar, K.; Krishnan, P.; Pieris, R. & Francis, E. (2007). Hybrid approach to surgical

Ten Cate, G.; Fosse, E.; Hol, P.K.; Samset, E.; Bock, R.W.; McKinsey, J.F.; Pearce, B.J. &

Tomaszewski, R. (2008). Planning a Better Operating Room Suite: Design and

Vahanian, A.; Alfieri, O.R.; Al-Attar, N. et al. (2008). Transcatheter valve implantation for

Walsh, S.R.; Tang, T.Y.; Sadat, U.; Naik, J.; Gaunt, M.E.; Boyle, J.R.; Hayes, P.D. & Varty, K.

Zhao, D.X.; Leacche, M.; Balaguer, J.M.; Boudoulas, K.D.; Damp, J.A.; Greelish, J.P. & Byrne,

*American College of Cardiology*, Vol.53, No.3, (January 2009), pp. 232–241

Vol.47, No.5, (May 2008), pp. 1094-1098, PII S0741-5214(07)01592-3

M. & Becker C.R., pp. 33-51, Springer Verlag

(March 2008), pp. 43–54, PII S1556-7931(07)00103-9

S0741-5214(04)00754-2

(July 2008), pp. 1-8

correction of tetralogy of Fallot in all patients with functioning Blalock Taussig shunts. *Catheterization Cardiovascular Interventions*, Vol.70, No.2, (August 2007), pp. 256-264 Strobel, N., Meissner, O.; Boese, J.; Brunner, T.; Heigl, B.; Hoheisel, M.; Lauritsch, G.; Nagel,

M.; Pfister, M. & Rührnschopf, E.P. (2009). Medical Radiology, 3D Imaging with Flat-Detector C-Arm Systems, In: *Multislice CT*, Reiser, M.F.; Takahashi, M.; Modic,

Lothert, M. (2004). Integrating surgery and radiology in one suite: a multicenter study. *Journal of Vascular Surgery*, Vol.40, No.3, (September 2004), pp. 494-499, PII

Implementation Strategies for Success. *Perioperative Nursing Clinics*, Vol.3, No.1,

patients with aortic stenosis: a position statement from the European Association of Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI). *European Journal of Cardio-Thoracic Surgery*, Vol.34, No.1,

(2008). Endovascular stenting versus open surgery for thoracic aortic disease: systematic review and metaanalysis of the results. *Journal of Vascular Surgery*,

J.G. (2009). Routine Intraoperative Completion Angiography After Coronary Artery Bypass Grafting and 1-Stop Hybrid Revascularization Results From a Fully Integrated Hybrid Catheterization Laboratory/Operating Room. *Journal of the*  The stenotic degenerative aortic valve disease is a slowly developing condition. This condition is the result of an active process. Recently, it has been discovered that programmed cell death plays a major role in this progression (1-4). Stenotic degenerative aortic valve disease obstructs the outflow of the left ventricle (LV) and causes a pressure overload, with all its undesirable consequences. Once the disease has become symptomatic, the prognosis without surgical replacement of the valve is dismal: the life expectancy is reduced to 2 or 3 years with occurrence of syncope, angina pectoris and certainly with dyspnea (5). Age, left ventricular dysfunction and neurologic condition played a major role in the denial for AVR (6). Medical treatment and balloon valvotomy (7) do not improve the prognosis. Aortic valve replacement (AVR) is the only way to prolong life and improve its quality. In spite of technical improvements, the procedure involves a major procedure, with all its complications. Moreover, one condition (the valve disease) is replaced by another (the prosthetic valve).

The possible hospital or 30 day complications which can occur after AVR include valve related, cardiac non-valve related and non-cardiac events. Identification of their predictors could lead to an improved referral pattern and, hence to an improved 30 day outcome, provided these predictors are liable to changes.

### **2. Methods**

In one centre for cardiac surgery, 1000 patients who underwent AVR with Carpentier-Edwards cardiac valve, were studied in a retrospective way. The operations were performed between the end of 1986 and the end of 2006. In most patients with degenerative aortic valve disease, coronary artery disease was also present. Hence, patients who received concomitant CABG were also included. Their median age was 75 (71-77) years. The surgical technique remained largely unchanged and was performed through a median sternotomy. After opening the pericardium, the ascending aorta, the vena cava inferior and superior could be accessed for connection to the extracorporeal circulation. The pulmonary artery was ligated temporarily in a gentle way. A vent was placed through the left superior pulmonary vein in

The 30 Day Complication Rate After Aortic Valve

Replacement with a Pericardial Valve in a Mainly Geriatric Population 109

40/68 by history and CT (computer tomography),

Left ventricular dysfunction 247 decrease documented by segmental analysis of

Atrial fibrillation 197 chronic or paroxysmal, documented by ECG

Conduction defect 270 documented by ECG: of any type and of any

Previous endocarditis 17 documented by bacteriological analysis during

Need for urgent AVR 25 condition needing AVR at the same day in

Aortoplasty 61 enlargement of reduction of the ascending aorta

endocarditis, documented by clinical signs, echocardiography and blood samples

thrombo-embolism, with neurological signs (n=25), documented on CT or ischemic

 congestive heart failure defined by the inability of the heart to maintain an adequate circulation without support of inotropics or assist device (n=36) conduction defects (new or progression of an pre-existing defect), documented on

bleeding, evident if external or documented on cerebral CT (n=20)

ventricular arrhythmias, documented on ECG (n=37)

ECG, of any type and of any degree (n=101)

Heart failure 216 at least one previous admission for pulmonary

ventricular wall on echocardiography

Ventricular arrhythmias 74 documented by Holter monitoring

 251 by anamnesis at admission for AVR Need for digitalis 152 by anamnesis at admission for AVR

Previous PaceMaker implant 33 during previous admission

 order for the patient to survive Cross-clamping>75 min 460 sum of cross clamping time for valve implantation and for additional procedures

Valve size 19 27 sizes ranging from 19 to 27

previous admission

Previous CABG 81 previous admission and operation protocol Carotid artery disease 238 stenosis of 40% or more on Doppler-duplex

History of TIA/CVA (Transient ischemic attack / cerbrovascular accident)

LV ejection fraction<50% 155 calculated by data obtained at

echocardiography

 edema NYHA (New York Heart Association) class IV

degree

33 ibid

First degree AV (atrioventricular) block

Concomitant CABG 610 Mitral ring 13

Carotid endarterectomy 22

The adverse events under scrutiny were

events on other locations (n=2)



(n=2)

during previous admission

order to decompress the left ventricle. Before the extracorporeal circulation was started, the patient was fully heparinized. The patient was cooled to 30° Celsius and the heart was stopped and topically cooled with sludge ice. Systemic blood pressure, central venous pressure and left atrial pressure were continuously monitored. The ascending aorta was opened and cold cardioplegia was instilled within the coronary arteries. In case of severe coronary artery disease, additional cardioplegia was instilled through the coronary sinus. This was repeated after 30 minutes. The calcified aortic valve was inspected and excised. The ring was decalcified if necessary. The interrupted sutures were placed as three separate series through the aortic annulus, and then through the prosthesis in the same order. The valve was lowered into the annulus and the sutures were tied and severed at the desired length. If necessary, the great saphenous vein was harvested by another team for concomitant CABG. The suturing of the bypass on the coronary arteries were performed during the same clamping. The aortotomy was closed with a double running suture and the proximal end of the bypasses were also connected. The internal mammary artery was not often used. The extracorporeal circulation was stopped stepwise and then disconnected. Temporary pacemaker wires were attached to the surface of the ventricles. After thorough hemostasis and placement of drains, the chest cavity was closed. The patient was transferred to the intensive care unit and kept under sedation for 24 hours. In 1996, the anesthesia changed into a "short-track" procedure: the sedation was shortened from one day to 6 hours and extubation was performed as soon as possible thereafter.

The changes is referral pattern were documented by comparison of age and co-morbid conditions in four periods of 5 year (1986-1991; 1992-1996; 1997-2001 and 2002-2006). A chisquare analysis was used as statistical analysis to show significant differences over time.

Twenty five preoperative and five peri-operative factors were screened in two steps. In a first step, the effect on hospital events was studied by an univariate chi-square or a Fisherexact analysis. In a second step, the significant factors were entered in a multivariate logistic regression analysis in order to identify the predictors.

The results are presented for each risk factor (first column of the table), n/N (second column), p or probability (third column), OR (fourth column) and 95%CI (last column), where N is the number of patients at risk (i.e. having the risk factor) and n the number of these patients who suffered the complication; OR is the odds ratio and 95%CI is the 95% confidence interval.

These factors were defined or dichotomized if appropriate and numbers are given.


order to decompress the left ventricle. Before the extracorporeal circulation was started, the patient was fully heparinized. The patient was cooled to 30° Celsius and the heart was stopped and topically cooled with sludge ice. Systemic blood pressure, central venous pressure and left atrial pressure were continuously monitored. The ascending aorta was opened and cold cardioplegia was instilled within the coronary arteries. In case of severe coronary artery disease, additional cardioplegia was instilled through the coronary sinus. This was repeated after 30 minutes. The calcified aortic valve was inspected and excised. The ring was decalcified if necessary. The interrupted sutures were placed as three separate series through the aortic annulus, and then through the prosthesis in the same order. The valve was lowered into the annulus and the sutures were tied and severed at the desired length. If necessary, the great saphenous vein was harvested by another team for concomitant CABG. The suturing of the bypass on the coronary arteries were performed during the same clamping. The aortotomy was closed with a double running suture and the proximal end of the bypasses were also connected. The internal mammary artery was not often used. The extracorporeal circulation was stopped stepwise and then disconnected. Temporary pacemaker wires were attached to the surface of the ventricles. After thorough hemostasis and placement of drains, the chest cavity was closed. The patient was transferred to the intensive care unit and kept under sedation for 24 hours. In 1996, the anesthesia changed into a "short-track" procedure: the sedation was shortened from one day to 6 hours

The changes is referral pattern were documented by comparison of age and co-morbid conditions in four periods of 5 year (1986-1991; 1992-1996; 1997-2001 and 2002-2006). A chisquare analysis was used as statistical analysis to show significant differences over time. Twenty five preoperative and five peri-operative factors were screened in two steps. In a first step, the effect on hospital events was studied by an univariate chi-square or a Fisherexact analysis. In a second step, the significant factors were entered in a multivariate logistic

The results are presented for each risk factor (first column of the table), n/N (second column), p or probability (third column), OR (fourth column) and 95%CI (last column), where N is the number of patients at risk (i.e. having the risk factor) and n the number of these patients who suffered the complication; OR is the odds ratio and 95%CI is the 95%

These factors were defined or dichotomized if appropriate and numbers are given.

 235 defined on protocol by pneumologist Impaired renal function 109 plasma creatinine over 1.3 mg%

Coronary artery disease 631 documented on coronarography

Previous carcinoma 104 proven by histologic examination and treated

Hypertension 654 blood pressure repeatedly over 140/90 mmHg

Diabetes 149 treated by diet, peroral antidiabetics or insulin

Myocardial infarction 151 documented by ECG, enzymes (during

and extubation was performed as soon as possible thereafter.

regression analysis in order to identify the predictors.

confidence interval.

Octogenarians 186 Male gender 530

COPD (chronic obstructive pulmonary disease)

with curative intent

in resting conditions

previous admission)


The adverse events under scrutiny were

	- endocarditis, documented by clinical signs, echocardiography and blood samples (n=2)
	- thrombo-embolism, with neurological signs (n=25), documented on CT or ischemic events on other locations (n=2)
	- bleeding, evident if external or documented on cerebral CT (n=20)
	- ventricular arrhythmias, documented on ECG (n=37)
	- congestive heart failure defined by the inability of the heart to maintain an adequate circulation without support of inotropics or assist device (n=36)
	- conduction defects (new or progression of an pre-existing defect), documented on ECG, of any type and of any degree (n=101)

The 30 Day Complication Rate After Aortic Valve

Multivariate analysis showed following results

responsible for these differences in mortality.

postoperative risk.

surgery on mortality(10). **Thromboembolic events** 

with a 95% confidence interval between 1.1-5.7.

Replacement with a Pericardial Valve in a Mainly Geriatric Population 111

**Factor n/N p OR 95%CI**  Urgent AVR 7/25 <0.001 9.0 2.8-28.7 Digitalis 12/152 0.002 3.5 1.6-7.7 Age > 80 17/186 0.005 3.1 1.4-6.6

Mortality in the hospital phase was the most important outcome. It varied between 1.5% (8) and 24% (9). These differences were due to large differences in patient characteristics such as age and co-morbid conditions. With a time span of almost 20 year between the first and the last publication, improvement in surgical techniques and peri-operative care could also be

In most series, the hospital mortality was below 10%. In series where the mortality was over 10%, several risk factors were usually present. Independent predictors for hospital mortality were identified and confirmed that specific co-morbid conditions increased the early

Most of these factors could be related to the left ventricle and hence to the patient. An emergency need for AVR (i.e. to operate on the same day as the admission in order for the patient to survive) has been identified as the most important predictor, with a increase of mortality of 10 times (10). This has been confirmed in other series (11,12). This indicated to an exhaustion of all compensatory mechanisms to maintain an adequate circulation. A need for urgent AVR has also been identified as a predictor for early postoperative congestive heart failure, which is a highly lethal condition (13). A high preoperative functional class NYHA IV (14,15) and a low-flow low-gradient problem also could be related to a protracted burden, and hence a decreased left ventricular function. Coronary artery disease, previous and the need for concomitant CABG (9,11,12,15) as well as a previous myocardial infarction

(10,11) and previous CABG (12) could add to a decrease in left ventricular function.

analysis identified a decreased left ventricular function (p<0.01) as sole risk factor.

Valvular factors such as severity of valvular disease and the type and size of valve prosthesis implanted also had an effect (15,16). The effect of non-cardiac factors such as diabetes (15) and renal disease (11,12,17) was also observed. Remarkably, the effect of age over 80 (9,12,18,19), although important, was less compared to the effect of need for urgent

TE events were one of the most important and devastating events after AVR, especially if permanent neurological deficit was present. One also has to keep in mind that many TE events go unnoticed. In one small series, MRI after cardiac surgery could document silent events in 6 of 34 patients, which is rather high (20). We found this clinically evident thromboembolism in 27 of 1000 patients. In 25 cases, this was neurological. An univariate

This risk factor was confirmed in a multivariate analysis, which showed an ejection fraction below 50% as an independent predictor (11/247 patients), with p=0.027, an odds ratio of 2.5

Some studies reported on the predictors for thromboembolism after AVR on long-term and none reported on such events on short-term. The short-term thromboembolic events, however, have their importance since these are a predictor for future events (21). A preoperative CVA seemed to have a comparable significance (21-24) for long-term events.

	- acute renal function impairment, documented by an increase of plasma creatinine with 0.3 mg% (n=53)
	- pulmonary complications: clinical and radiological signs of atelectasis or respiratory infection or prolonged intubation (n=58).
