Stephen Brecker

Long-term outcomes after transcatheter aortic valve implantation in high-risk patients with severe aortic stenosis: the U.K. TAVI (United Kingdom Transcatheter Aortic Valve Implantation) Registry.

OBJECTIVES The objective was to define the characteristics of a real-world patient population treated with transcatheter aortic valve implantation (TAVI), regardless of technology or access route, and to evaluate their clinical outcome over the mid to long term. BACKGROUND Although a substantial body of data exists in relation to early clinical outcomes after TAVI, there are few data on outcomes beyond 1 year in any notable number of patients. METHODS The U.K. TAVI (United Kingdom Transcatheter Aortic Valve Implantation) Registry was established to report outcomes of all TAVI procedures performed within the United Kingdom. Data were collected prospectively on 870 patients undergoing 877 TAVI procedures up until December 31, 2009. Mortality tracking was achieved in 100% of patients with mortality status reported as of December 2010. RESULTS Survival at 30 days was 92.9%, and it was 78.6% and 73.7% at 1 year and 2 years, respectively. There was a marked attrition in survival between 30 days and 1 year. In a univariate model, survival was significantly adversely affected by renal dysfunction, the presence of coronary artery disease, and a nontransfemoral approach; whereas left ventricular function (ejection fraction <30%), the presence of moderate/severe aortic regurgitation, and chronic obstructive pulmonary disease remained the only independent predictors of mortality in the multivariate model. CONCLUSIONS Midterm to long-term survival after TAVI was encouraging in this high-risk patient population, although a substantial proportion of patients died within the first year.

Coronary artery bypass surgery versus percutaneous coronary intervention with stent implantation in patients with multivessel coronary artery disease (the Stent or Surgery trial): a randomised controlled trial

BACKGROUND: Results of trials, comparing percutaneous transluminal coronary angioplasty (PTCA) with coronary artery bypass grafting (CABG), indicate that rates of death or myocardial infarction are similar with either treatment strategy. Management with PTCA is, however, associated with an increased requirement for subsequent, additional revascularisation. Coronary stents, used as an adjunct to PTCA, reduce restenosis and the need for repeat revascularisation. The aim of the Stent or Surgery (SoS) trial was to assess the effect of stent-assisted percutaneous coronary intervention (PCI) versus CABG in the management of patients with multivessel disease. METHODS: In 53 centres in Europe and Canada, symptomatic patients with multivessel coronary artery disease were randomised to CABG (n=500) or stent-assisted PCI (n=488). The primary outcome measure was a comparison of the rates of repeat revascularisation. Secondary outcomes included death or Q-wave myocardial infarction and all-cause mortality. Analysis was by intention to treat. FINDINGS: All patients were followed-up for a minimum of 1 year and the results are expressed for the median follow-up of 2 years. 21% (n=101) of patients in the PCI group required additional revascularisation procedures compared with 6% (n=30) in the CABG group (hazard ratio 3.85, 95% CI 2.56-5.79, p<0.0001). The incidence of death or Q-wave myocardial infarction was similar in both groups (PCI 9% [n=46], CABG 10% [n=49]; hazard ratio 0.95, 95% CI 0.63-1.42, p=0.80). There were fewer deaths in the CABG group than in the PCI group (PCI 5% [n=22], CABG 2% [n=8]; hazard ratio 2.91, 95% CI 1.29-6.53, p=0.01). INTERPRETATION: The use of coronary stents has reduced the need for repeat revascularisation when compared with previous studies that used balloon angioplasty, though the rate remains significantly higher than in patients managed with CABG. The apparent reduction in mortality with CABG requires further investigation.BACKGROUND Results of trials, comparing percutaneous transluminal coronary angioplasty (PTCA) with coronary artery bypass grafting (CABG), indicate that rates of death or myocardial infarction are similar with either treatment strategy. Management with PTCA is, however, associated with an increased requirement for subsequent, additional revascularisation. Coronary stents, used as an adjunct to PTCA, reduce restenosis and the need for repeat revascularisation. The aim of the Stent or Surgery (SoS) trial was to assess the effect of stent-assisted percutaneous coronary intervention (PCI) versus CABG in the management of patients with multivessel disease. METHODS In 53 centres in Europe and Canada, symptomatic patients with multivessel coronary artery disease were randomised to CABG (n=500) or stent-assisted PCI (n=488). The primary outcome measure was a comparison of the rates of repeat revascularisation. Secondary outcomes included death or Q-wave myocardial infarction and all-cause mortality. Analysis was by intention to treat. FINDINGS All patients were followed-up for a minimum of 1 year and the results are expressed for the median follow-up of 2 years. 21% (n=101) of patients in the PCI group required additional revascularisation procedures compared with 6% (n=30) in the CABG group (hazard ratio 3.85, 95% CI 2.56-5.79, p<0.0001). The incidence of death or Q-wave myocardial infarction was similar in both groups (PCI 9% [n=46], CABG 10% [n=49]; hazard ratio 0.95, 95% CI 0.63-1.42, p=0.80). There were fewer deaths in the CABG group than in the PCI group (PCI 5% [n=22], CABG 2% [n=8]; hazard ratio 2.91, 95% CI 1.29-6.53, p=0.01). INTERPRETATION The use of coronary stents has reduced the need for repeat revascularisation when compared with previous studies that used balloon angioplasty, though the rate remains significantly higher than in patients managed with CABG. The apparent reduction in mortality with CABG requires further investigation.

Effects of dual-chamber pacing with short atrioventricular delay in dilated cardiomyopathy

Mitral or tricuspid regurgitation of long duration may so shorten the ventricular filling time in dilated cardiomyopathy that stroke volume is limited. We assessed the effects of changing the atrioventricular interval during temporary or permanent dual-chamber DDD pacing in twelve dilated cardiomyopathy patients with short ventricular filling times due to regurgitation. We measured ventricular filling time and cardiac output with doppler echocardiography and exercise capacity on a treadmill, at baseline and with the best atrioventricular delay during pacing. The durations of both mitral and tricuspid regurgitation were significantly shorter at the shorter atrioventricular interval (mean reductions 85 [95% CI 60-110] ms and 110 [75-150] ms, respectively; p < 0.001 for both). There were consequent increases in left-ventricular and right-ventricular filling times (65 [35-95] ms and 90 [60-120] ms, p < 0.001). For each 50 ms reduction in atrioventricular delay, left-ventricular filling time increased by 35 ms in six subjects with presystolic mitral regurgitation and right-ventricular filling time by 30 ms in nine subjects with presystolic tricuspid regurgitation. At the short atrioventricular interval, cardiac output was greater than baseline (by 1.1 [0.8-1.4] l/min, p < 0.01) and there were rises in exercise duration (104 [45-165] s, p < 0.05) and maximum oxygen consumption (2.1 [1.5-2.7] ml kg-1 min-1, p < 0.05). There was a decrease in the Likert visual analogue score of breathlessness at peak exercise (8.6 [SD 2.1] vs 4.9 [3.1], p < 0.01). Although from a small sample, these findings suggest that DDD pacing with a short atrioventricular delay may have therapeutic potential in patients with dilated cardiomyopathy, even in the absence of conventional indications for pacemaker implantation.

Transcatheter Aortic Valve Implantation in Failed Bioprosthetic Surgical Valves

IMPORTANCE Owing to a considerable shift toward bioprosthesis implantation rather than mechanical valves, it is expected that patients will increasingly present with degenerated bioprostheses in the next few years. Transcatheter aortic valve-in-valve implantation is a less invasive approach for patients with structural valve deterioration; however, a comprehensive evaluation of survival after the procedure has not yet been performed. OBJECTIVE To determine the survival of patients after transcatheter valve-in-valve implantation inside failed surgical bioprosthetic valves. DESIGN, SETTING, AND PARTICIPANTS Correlates for survival were evaluated using a multinational valve-in-valve registry that included 459 patients with degenerated bioprosthetic valves undergoing valve-in-valve implantation between 2007 and May 2013 in 55 centers (mean age, 77.6 [SD, 9.8] years; 56% men; median Society of Thoracic Surgeons mortality prediction score, 9.8% [interquartile range, 7.7%-16%]). Surgical valves were classified as small (≤21 mm; 29.7%), intermediate (>21 and <25 mm; 39.3%), and large (≥25 mm; 31%). Implanted devices included both balloon- and self-expandable valves. MAIN OUTCOMES AND MEASURES Survival, stroke, and New York Heart Association functional class. RESULTS Modes of bioprosthesis failure were stenosis (n = 181 [39.4%]), regurgitation (n = 139 [30.3%]), and combined (n = 139 [30.3%]). The stenosis group had a higher percentage of small valves (37% vs 20.9% and 26.6% in the regurgitation and combined groups, respectively; P = .005). Within 1 month following valve-in-valve implantation, 35 (7.6%) patients died, 8 (1.7%) had major stroke, and 313 (92.6%) of surviving patients had good functional status (New York Heart Association class I/II). The overall 1-year Kaplan-Meier survival rate was 83.2% (95% CI, 80.8%-84.7%; 62 death events; 228 survivors). Patients in the stenosis group had worse 1-year survival (76.6%; 95% CI, 68.9%-83.1%; 34 deaths; 86 survivors) in comparison with the regurgitation group (91.2%; 95% CI, 85.7%-96.7%; 10 deaths; 76 survivors) and the combined group (83.9%; 95% CI, 76.8%-91%; 18 deaths; 66 survivors) (P = .01). Similarly, patients with small valves had worse 1-year survival (74.8% [95% CI, 66.2%-83.4%]; 27 deaths; 57 survivors) vs with intermediate-sized valves (81.8%; 95% CI, 75.3%-88.3%; 26 deaths; 92 survivors) and with large valves (93.3%; 95% CI, 85.7%-96.7%; 7 deaths; 73 survivors) (P = .001). Factors associated with mortality within 1 year included having small surgical bioprosthesis (≤21 mm; hazard ratio, 2.04; 95% CI, 1.14-3.67; P = .02) and baseline stenosis (vs regurgitation; hazard ratio, 3.07; 95% CI, 1.33-7.08; P = .008). CONCLUSIONS AND RELEVANCE In this registry of patients who underwent transcatheter valve-in-valve implantation for degenerated bioprosthetic aortic valves, overall 1-year survival was 83.2%. Survival was lower among patients with small bioprostheses and those with predominant surgical valve stenosis.

Transcatheter Aortic Valve Replacement for Degenerative Bioprosthetic Surgical Valves: Results from the Global Valve-in-Valve Registry

Background— Transcatheter aortic valve-in-valve implantation is an emerging therapeutic alternative for patients with a failed surgical bioprosthesis and may obviate the need for reoperation. We evaluated the clinical results of this technique using a large, worldwide registry. Methods and Results— The Global Valve-in-Valve Registry included 202 patients with degenerated bioprosthetic valves (aged 77.7±10.4 years; 52.5% men) from 38 cardiac centers. Bioprosthesis mode of failure was stenosis (n=85; 42%), regurgitation (n=68; 34%), or combined stenosis and regurgitation (n=49; 24%). Implanted devices included CoreValve (n=124) and Edwards SAPIEN (n=78). Procedural success was achieved in 93.1% of cases. Adverse procedural outcomes included initial device malposition in 15.3% of cases and ostial coronary obstruction in 3.5%. After the procedure, valve maximum/mean gradients were 28.4±14.1/15.9±8.6 mm Hg, and 95% of patients had ≤+1 degree of aortic regurgitation. At 30-day follow-up, all-cause mortality was 8.4%, and 84.1% of patients were at New York Heart Association functional class I/II. One-year follow-up was obtained in 87 patients, with 85.8% survival of treated patients. Conclusions— The valve-in-valve procedure is clinically effective in the vast majority of patients with degenerated bioprosthetic valves. Safety and efficacy concerns include device malposition, ostial coronary obstruction, and high gradients after the procedure. # Clinical Perspective {#article-title-38}Background— Transcatheter aortic valve-in-valve implantation is an emerging therapeutic alternative for patients with a failed surgical bioprosthesis and may obviate the need for reoperation. We evaluated the clinical results of this technique using a large, worldwide registry. Methods and Results— The Global Valve-in-Valve Registry included 202 patients with degenerated bioprosthetic valves (aged 77.7±10.4 years; 52.5% men) from 38 cardiac centers. Bioprosthesis mode of failure was stenosis (n=85; 42%), regurgitation (n=68; 34%), or combined stenosis and regurgitation (n=49; 24%). Implanted devices included CoreValve (n=124) and Edwards SAPIEN (n=78). Procedural success was achieved in 93.1% of cases. Adverse procedural outcomes included initial device malposition in 15.3% of cases and ostial coronary obstruction in 3.5%. After the procedure, valve maximum/mean gradients were 28.4±14.1/15.9±8.6 mm Hg, and 95% of patients had ⩽+1 degree of aortic regurgitation. At 30-day follow-up, all-cause mortality was 8.4%, and 84.1% of patients were at New York Heart Association functional class I/II. One-year follow-up was obtained in 87 patients, with 85.8% survival of treated patients. Conclusions— The valve-in-valve procedure is clinically effective in the vast majority of patients with degenerated bioprosthetic valves. Safety and efficacy concerns include device malposition, ostial coronary obstruction, and high gradients after the procedure.

Effects of abnormal activation on the time course of the left ventricular pressure pulse in dilated cardiomyopathy

Objective—To investigate the effects of QRS duration on characteristics of the left ventricular pressure pulse derived from the time course of functional mitral regurgitation by continuous wave Doppler. Design—Retrospective and prospective study of 50 patients with dilated cardiomyopathy, by electrocardiography, echocardiography, and Doppler cardiography. Setting—Tertiary cardiac referral centre. Patients—50 patients (mean age (SD) 58 (16)) with dilated cardiomyopathy, all with functional mitral regurgitation. Results—The values of QRS duration ranged widely, from 70 to 190 ms with a mean value of 110 ms, and were unimodally distributed. The overall duration of mitral regurgitation correlated positively with QRS time (r=0·65) over the entire range of values. When the duration of mitral regurgitation was divided into contraction, aortic ejection, and relaxation times, increased QRS duration prolonged contraction (r=0·51) and relaxation (r=0·52) times. Aortic ejection time was affected by RR interval (r=0·74). Duration of QRS correlated negatively with peak rate of rise in left ventricular pressure (+dP/dt) (r=−0·48), and positively with the time intervals from Q to peak pressure (r=0·49) and to peak +dP/dt (r=0·72), and also with those from the start of mitral regurgitation to peak pressure (r=0·49) and to peak +dP/dt (r=0·76). Duration of QRS did not directly affect the peak rate of left ventricular pressure fall (−dP/dt), or the isovolumic relaxation period. Conclusions—Values of QRS duration are unimodally distributed in patients with dilated cardiomyopathy, without evidence of a discrete group of patients with left bundle branch block. Prolonged QRS duration reduces peak +dP/dt, prolongs overall duration of the pressure pulse, the time to peak +dP/dt, and relaxation time. Duration of QRS must therefore be taken into account in assessing standard measurements of myocardial function in patients with dilated cardiomyopathy.

Transcatheter Aortic Valve Implantation for Pure Severe Native Aortic Valve Regurgitation

OBJECTIVES This study sought to collect data and evaluate the anecdotal use of transcatheter aortic valve implantation (TAVI) in pure native aortic valve regurgitation (NAVR) for patients who were deemed surgically inoperable BACKGROUND Data and experience with TAVI in the treatment of patients with pure severe NAVR are limited. METHODS Data on baseline patient characteristics, device and procedure parameters, echocardiographic parameters, and outcomes up to July 2012 were collected retrospectively from 14 centers that have performed TAVI for NAVR. RESULTS A total of 43 patients underwent TAVI with the CoreValve prosthesis (Medtronic, Minneapolis, Minnesota) at 14 centers (mean age, 75.3 ± 8.8 years; 53% female; mean logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation), 26.9 ± 17.9%; and mean Society of Thoracic Surgeons score, 10.2 ± 5.3%). All patients had severe NAVR on echocardiography without aortic stenosis and 17 patients (39.5%) had the degree of aortic valvular calcification documented on CT or echocardiography. Vascular access was transfemoral (n = 35), subclavian (n = 4), direct aortic (n = 3), and carotid (n = 1). Implantation of a TAVI was performed in 42 patients (97.7%), and 8 patients (18.6%) required a second valve during the index procedure for residual aortic regurgitation. In all patients requiring second valves, valvular calcification was absent (p = 0.014). Post-procedure aortic regurgitation grade I or lower was present in 34 patients (79.1%). At 30 days, the major stroke incidence was 4.7%, and the all-cause mortality rate was 9.3%. At 12 months, the all-cause mortality rate was 21.4% (6 of 28 patients). CONCLUSIONS This registry analysis demonstrates the feasibility and potential procedure difficulties when using TAVI for severe NAVR. Acceptable results may be achieved in carefully selected patients who are deemed too high risk for conventional surgery, but the possibility of requiring 2 valves and leaving residual aortic regurgitation remain important considerations.

Differing effects of right ventricular pacing and left bundle branch block on left ventricular function.

OBJECTIVE--To compare the different effects of right ventricular pacing and classic left bundle branch block on left ventricular function. DESIGN--Retrospective and prospective study of 48 patients by electrocardiography, and M mode, cross sectional, and Doppler echocardiography. SETTING--A tertiary cardiac referral centre. PATIENTS--48 patients (age range 21 to 89 years, 15 women), 24 with a VVI pacemaker implanted and 24 with classic left bundle branch block. Functional mitral regurgitation was present in all those with right ventricular pacing and 22 of those with left bundle branch block. RESULTS--Age, RR interval, and left ventricular size were similar in the two groups, as were conventional measurements of overall systolic function: shortening fraction and pre-ejection and aortic ejection times. In right ventricular pacing, however, QRS duration (p < 0.01) and electromechanical delay were much longer (p < 0.001), whereas the time intervals from onset of mitral regurgitation to aortic opening (contraction time) and from A 2 to the end of mitral regurgitation (relaxation time) were consistently shorter (p < 0.01) than corresponding values in patients with left bundle branch block. Reversed splitting of the second heart sound was much commoner in left bundle branch block (p < 0.02), and only these patients showed an early systolic ventricular septal contraction. Its onset followed the initial deflection of the QRS complex by 40(15) ms and preceded mitral regurgitation by a small but consistent interval of 10 ms (p < 0.01). The onset of posterior wall thickening was synchronous with the onset of mitral regurgitation in right ventricular pacing but much later (p < 0.01) in patients with left bundle branch block. The extent of incoordinate wall motion measure as relative dimension change during pre-ejection and isovolumic relaxation period was much greater (p < 0.01) in left bundle branch block. These major differences were not altered by left ventricular cavity size in either group, nor by the presence of previous left bundle branch block in patients who were subsequently paced. CONCLUSIONS--The left ventricle seems to be activated much more rapidly with right ventricular pacing than with left bundle branch block. This applies even when left bundle branch block is present before pacing. Electromechanical delay, contraction and relaxation times, and extent of incoordinate ventricular wall motion differ strikingly between the two conditions. The use of right ventricular pacing as an experimental model of left bundle branch block in humans must be re-examined.

Treatment of Symptomatic Severe Aortic Stenosis With a Novel Resheathable Supra-Annular Self-Expanding Transcatheter Aortic Valve System

OBJECTIVES The purpose of this study was to prospectively evaluate the safety and clinical performance of the CoreValve Evolut R transcatheter aortic valve replacement (TAVR) system (Medtronic, Inc., Minneapolis, Minnesota) in a single-arm, multicenter pivotal study in high- or extreme-risk patients with symptomatic aortic valve stenosis. BACKGROUND Although outcomes following TAVR are improving, challenges still exist. The repositionable 14-F equivalent CoreValve Evolut R TAVR system was developed to mitigate some of these challenges. METHODS Suitable patients (n = 60) underwent TAVR with a 26- or 29-mm Evolut R valve. Primary safety endpoints were mortality and stroke at 30 days. Primary clinical performance endpoints were device success per the VARC-2 (Valve Academic Research Consortium-2) and the percent of patients with mild or less aortic regurgitation 24 h to 7 days post-procedure. RESULTS Patients (66.7% female; mean age 82.8 ± 6.1 years; Society of Thoracic Surgeons Score 7.0 ± 3.7%) underwent TAVR via the transfemoral route in 98.3%, using a 29-mm valve in 68.3% of patients. All attempts at repositioning were successful. No death or stroke was observed up to 30 days. The VARC-2 overall device success rate was 78.6%. Paravalvular regurgitation post TAVR was mild or less in 96.6%, moderate in 3.4%, and severe in 0% at 30 days. Major vascular complications occurred in 8.3%, and permanent pacemaker implantation was required in 11.7% of patients. CONCLUSIONS The repositionable 14-F equivalent Evolut R TAVR system is safe and effective at treating high-risk symptomatic aortic stenosis patients. Repositioning was successful when required in all patients, with low rates of moderate or severe paravalvular aortic regurgitation and low permanent pacemaker implantation. (The Medtronic CoreValve™ Evolut R™ CE Mark Clinical Study; NCT01876420).

Left ventricular filling characteristics in pulmonary hypertension: a new mode of ventricular interaction

Objective—To examine the effects of pulmonary hypertension on left ventricular diastolic function and to relate the findings to possible mechanisms of interdependence between the right and left sides of the heart in ventricular disease. Design—A retrospective and prospective analysis of echocardiographic and Doppler studies. Setting—A tertiary referral centre for both cardiac and pulmonary disease. Patients—29 patients with pulmonary hypertension (12 primary pulmonary hypertension, 10 pulmonary fibrosis, five atrial septal defect (ASD), and two scleroderma) were compared with a control group of 10 patients with an enlarged right ventricle but normal pulmonary artery pressure (six ASD, one after ASD closure, one ASD and pulmonary valvotomy, one tricuspid valve endocarditis and repair, and one pulmonary fibrosis). None had clinical or echocardiographic evidence of intrinsic left ventricular disease. Main Outcome measures—M mode echocardiographic measurements were made of septal thickness, and left and right ventricular internal cavity dimensions. Doppler derived right ventricular to right atrial pressure drop, and time intervals were measured, as were isovolumic relaxation time, and Doppler left ventricular filling characteristics. Results—The peak right ventricular to right atrial pressure gradient was (mean (SD)) 60 (16) mm Hg in pulmonary hypertensive patients, and 18 (5) mm Hg in controls. The time intervals P2 to the end of the tricuspid regurgitation, and P2 to the start of tricuspid flow were both prolonged in patients with pulmonary hypertension compared with controls (115 (60) and 120 (40) ν 40 (15) and 45 (10) ms, p values <0·001). Pulmonary hypertensive patients commonly had a dominant A wave on the transmitral Doppler (23/29); however, all the controls had a dominant E wave. Isovolumic relaxation time of the left ventricle was prolonged in pulmonary hypertensive patients compared with controls, measured as both A2 to mitral valve opening (80 (25) ν 50 (15) ms) and as A2 to the start of mitral flow (105 (30) ν 60 (15) ms, p values <0·001). The delay from mitral valve opening to the start of transmitral flow was longer in patients with pulmonary hypertension (30 (15) ms) compared with controls (10 (10) ms, p < 0·001). At the time of mitral opening there was a right ventricular to right atrial gradient of 12 (10) mm Hg in pulmonary hypertensive patients, but this was negligible in controls (0·4 (0·3) mm Hg, p < 0·001). Conclusions—Prolonged decline of right ventricular tension, the direct result of severe pulmonary hypertension, may appear as prolonged tricuspid regurgitation. It persists until after mitral valve opening on the left side of the heart, where events during isovolumic relaxation are disorganised, and subsequent filling is impaired. These effects are likely to be mediated through the interventricular septum, and this right-left ventricular asynchrony may represent a hitherto unrecognised mode of ventricular interaction.