**5. Complications of TAVR**

TAVR has seen an overall decline in peri-procedural complications over time, partly owing to newer technology and expertise.

Complications associated with TAVR are as listed in **Table 6**.

According to transcatheter valve therapy (TVT data), 30-day in-hospital mortality has decreased from 7.5% in 2012 to 4.6% in 2015 [15].

This part of the chapter briefly reviews about important complications post TAVR.

#### **5.1 Major vascular access site complications**

Access site complications incidence depends upon the method of localization and the location of the puncture site, the need for multiple punctures and the size of the sheath used. The incidence of major vascular complications showed a decreasing trend attributed to technical innovations reducing sheath size and valve delivery systems.

The overall major vascular complication rate was 17% in PARTNER 1 trial, decreased to 2.5% in low-risk TAVR trial [11], 2018 due to improvements in the sheath and valve delivery systems.

#### **5.2 Permanent pacemaker implantation (PPI)**

Need for PPI arises due to a complex interaction of the valve with the conduction system.

The incidence of PPI has not decreased as expected, compared with other complications. Changes in the valve design to prevent PVL and position of valve implantation contributed for PPI.

PPI incidence appears to increase with the oversizing of the valve and changes in valve design to prevent PVL. Shallow implantation and improvement in technical skill could decrease the incidence of PVL as shown in the REPRISE trial.

PPI frequency varies in relation to the valve type used. Balloon Expandable valve has a relatively less incidence of PPI at the cost of higher valvular gradients.

The incidence of new PPI post-TAVR was 6–10% in PARTNER 1 and PARTNER 2 trials which is similar to 5% seen in low-risk TAVR study [11].

The requirement of PPI has been associated with increased hospital stay and financial burden but has not been shown to increase mortality conclusively.

#### **5.3 Paravalvular leak (PVL)**

PVL occurs because of the difference in the shape of the valve which is circular compared to the elliptical aortic annulus.

The incidence of PVL is consistently shown to be higher with TAVR than SAVR in all landmark trials of TAVR.

Valve size, aortic valve distribution of calcium and implantation depth were predictive of post TAVR PVL [16].

Precise annulus sizing by appropriate aortic imaging pre-TAVR is fundamental to prevent PVL. With the use of newer imaging technology and understanding of the factors involved the incidence of moderate or severe PVL decreased 12.5% in PARTNER B to <1% in low-risk TAVR data [11]. Out of 12.5% moderate to severe PVL in PARTNER cohort B only 0.7% have severe leak, severe PVL causing an increase in mortality or need for re-intervention is very rare.

#### **5.4 Stroke**

Stroke is one of the most devastating complication post-TAVR, it causes an increase in mortality, significant worsening of quality of life and disability.

A stroke occurs due to the embolization of plaque contents from atheroma disrupted during delivery system manipulations. Early trial PARTNER 1 used a balloon-expandable valve with a 22-24F delivery catheter and showed a 30-day stroke risk of 5.5–6.2% [7].

The risk of stroke decreased over the years with increasing operator experience, advancements in valve technology, and improvement in patient selection.

PARTNER 2 and CoreValve studies used Sapien XT and CoreValve which used 18F delivery catheter and showed a 30-day risk of stroke around 4% [17–19].

A study on the timing of stroke post-TAVR by Samir et al. showed that of strokes occurring within 30 days post-TAVR, 64% were diagnosed within 2 days and 85% were diagnosed within 1 week, the risk of stroke after the initial peri-procedural period is not high [20]. More balloon post dilations and lack of dual antiplatelet therapy before the procedure were associated with a higher risk of early stroke [20].

**59**

*Transcatheter Aortic Valve Replacement: Clinical Indications and Outcomes*

ing from an intrinsic abnormality leading to an intervention.

an appearance of new valvular regurgitation constitutes SVD.

(overall VHD) and 2.8% within the first year (early VHD) [21].

Newer advances like Sentinel cerebral protection system are recently approved

The Sentinel study investigated the role of Sentinel CPS (cerebral protection system) but failed to show a reduction in the median total new lesion volume on MRI. So In view of the lack of robust evidence regarding the efficacy of CPS, the choice of using neuroprotection in TAVR requires an individualized risk-benefit

Investigations therapies like protecting aortic arch vessels with CPS, excluding the LAA and refining post procedural antithrombotic strategy may aid in a further

Structural valve deterioration is defined as any change in valve function result-

Rising interest for the use of TAVR in low-risk population makes durability of valve an important concern where the life expectancy of the patients would be more than 15 years. Five-year data from PARTNER 1 trial showed stable valve area and mean transvalvular gradient throughout the follow-up. The mean valve area was

Any increase in valvular gradients should warrant imaging workup for valve thrombosis. Data from multicentre registry showed, an incidence of VHD of 4.5%

leaflet motion (RELM) in transcatheter valves, evaluated by four-dimensional volume-rendered computer tomography [22]. The effect of this finding on clinical

Makkar et al. reported hypo-attenuated leaflet thickening (HALT) and reduced

Walksman et al. reported a 14% incidence of HALT and 11.2% RELM at 30 days

Multivariate analysis showed the absence of anticoagulation at discharge, valve size <23 mm, a valve in valve procedure and greater BMI as predictors of transcath-

Non-existent with self-expandable valves except in cases where pre or post-

Because of the use of newer imaging modalities accurate sizing of the balloon,

Device embolization was defined as, Movement of valve prosthesis during or after deployment such that it loses contact with the aortic annulus. A study by Makkar et al., out of 2,554 patients who underwent TAVR, valve embolization was noted in 1% of patients. Technical factors like undersized valve and complex aortic valve anatomy, incomplete balloon inflation, and pacing failure were associated

Increase in a mean gradient to >20 mm Hg or increase >10 mm Hg from baseline,

and the mean gradient was 10 mm Hg at 5 years and no events of clinical

*DOI: http://dx.doi.org/10.5772/intechopen.84909*

reduction in stroke incidence.

thrombosis of the TAVR valve [7].

outcomes needs further investigation.

**5.6 Miscellaneous**

*5.6.1 Annular rupture*

dilation is performed.

*5.6.2 Valve embolization*

with valve embolization [23].

post-TAVR, but were asymptomatic clinically.

an annular rupture is a very rare phenomenon.

eter valve hemodynamic deterioration post-TAVR [21].

analysis.

1.52 cm2

**5.5 Durability**

by the US FDA and are commercially available.

#### *Transcatheter Aortic Valve Replacement: Clinical Indications and Outcomes DOI: http://dx.doi.org/10.5772/intechopen.84909*

Newer advances like Sentinel cerebral protection system are recently approved by the US FDA and are commercially available.

The Sentinel study investigated the role of Sentinel CPS (cerebral protection system) but failed to show a reduction in the median total new lesion volume on MRI. So In view of the lack of robust evidence regarding the efficacy of CPS, the choice of using neuroprotection in TAVR requires an individualized risk-benefit analysis.

Investigations therapies like protecting aortic arch vessels with CPS, excluding the LAA and refining post procedural antithrombotic strategy may aid in a further reduction in stroke incidence.

#### **5.5 Durability**

*Aortic Stenosis - Current Perspectives*

sheath and valve delivery systems.

implantation contributed for PPI.

**5.3 Paravalvular leak (PVL)**

in all landmark trials of TAVR.

stroke risk of 5.5–6.2% [7].

predictive of post TAVR PVL [16].

compared to the elliptical aortic annulus.

system.

**5.2 Permanent pacemaker implantation (PPI)**

The overall major vascular complication rate was 17% in PARTNER 1 trial, decreased to 2.5% in low-risk TAVR trial [11], 2018 due to improvements in the

Need for PPI arises due to a complex interaction of the valve with the conduction

PPI incidence appears to increase with the oversizing of the valve and changes in valve design to prevent PVL. Shallow implantation and improvement in technical

PPI frequency varies in relation to the valve type used. Balloon Expandable valve

The incidence of new PPI post-TAVR was 6–10% in PARTNER 1 and PARTNER

The requirement of PPI has been associated with increased hospital stay and

PVL occurs because of the difference in the shape of the valve which is circular

The incidence of PVL is consistently shown to be higher with TAVR than SAVR

Precise annulus sizing by appropriate aortic imaging pre-TAVR is fundamental to prevent PVL. With the use of newer imaging technology and understanding of the factors involved the incidence of moderate or severe PVL decreased 12.5% in PARTNER B to <1% in low-risk TAVR data [11]. Out of 12.5% moderate to severe PVL in PARTNER cohort B only 0.7% have severe leak, severe PVL causing an

Valve size, aortic valve distribution of calcium and implantation depth were

Stroke is one of the most devastating complication post-TAVR, it causes an increase in mortality, significant worsening of quality of life and disability. A stroke occurs due to the embolization of plaque contents from atheroma disrupted during delivery system manipulations. Early trial PARTNER 1 used a balloon-expandable valve with a 22-24F delivery catheter and showed a 30-day

The risk of stroke decreased over the years with increasing operator experience,

PARTNER 2 and CoreValve studies used Sapien XT and CoreValve which used

A study on the timing of stroke post-TAVR by Samir et al. showed that of strokes occurring within 30 days post-TAVR, 64% were diagnosed within 2 days and 85% were diagnosed within 1 week, the risk of stroke after the initial peri-procedural period is not high [20]. More balloon post dilations and lack of dual antiplatelet therapy before the procedure were associated with a higher risk of early stroke [20].

advancements in valve technology, and improvement in patient selection.

18F delivery catheter and showed a 30-day risk of stroke around 4% [17–19].

The incidence of PPI has not decreased as expected, compared with other complications. Changes in the valve design to prevent PVL and position of valve

skill could decrease the incidence of PVL as shown in the REPRISE trial.

2 trials which is similar to 5% seen in low-risk TAVR study [11].

increase in mortality or need for re-intervention is very rare.

has a relatively less incidence of PPI at the cost of higher valvular gradients.

financial burden but has not been shown to increase mortality conclusively.

**58**

**5.4 Stroke**

Structural valve deterioration is defined as any change in valve function resulting from an intrinsic abnormality leading to an intervention.

Increase in a mean gradient to >20 mm Hg or increase >10 mm Hg from baseline, an appearance of new valvular regurgitation constitutes SVD.

Rising interest for the use of TAVR in low-risk population makes durability of valve an important concern where the life expectancy of the patients would be more than 15 years. Five-year data from PARTNER 1 trial showed stable valve area and mean transvalvular gradient throughout the follow-up. The mean valve area was 1.52 cm2 and the mean gradient was 10 mm Hg at 5 years and no events of clinical thrombosis of the TAVR valve [7].

Any increase in valvular gradients should warrant imaging workup for valve thrombosis. Data from multicentre registry showed, an incidence of VHD of 4.5% (overall VHD) and 2.8% within the first year (early VHD) [21].

Makkar et al. reported hypo-attenuated leaflet thickening (HALT) and reduced leaflet motion (RELM) in transcatheter valves, evaluated by four-dimensional volume-rendered computer tomography [22]. The effect of this finding on clinical outcomes needs further investigation.

Walksman et al. reported a 14% incidence of HALT and 11.2% RELM at 30 days post-TAVR, but were asymptomatic clinically.

Multivariate analysis showed the absence of anticoagulation at discharge, valve size <23 mm, a valve in valve procedure and greater BMI as predictors of transcatheter valve hemodynamic deterioration post-TAVR [21].

#### **5.6 Miscellaneous**

#### *5.6.1 Annular rupture*

Non-existent with self-expandable valves except in cases where pre or postdilation is performed.

Because of the use of newer imaging modalities accurate sizing of the balloon, an annular rupture is a very rare phenomenon.

#### *5.6.2 Valve embolization*

Device embolization was defined as, Movement of valve prosthesis during or after deployment such that it loses contact with the aortic annulus. A study by Makkar et al., out of 2,554 patients who underwent TAVR, valve embolization was noted in 1% of patients. Technical factors like undersized valve and complex aortic valve anatomy, incomplete balloon inflation, and pacing failure were associated with valve embolization [23].
