Rihal, Charanjit S.

AbstractIntroductionThree‐dimensional (3D) prototyping is a novel technology which can be used to plan and guide complex procedures such as transcatheter mitral valve replacement (TMVR).MethodsEight patients with severe mitral annular calcification (MAC) underwent TMVR. 3D digital models with digital balloon expandable valves were created from pre‐procedure CT scans using dedicated software. Five models were printed. These models were used to assess prosthesis sizing, anchoring, expansion, paravalvular gaps, left ventricular outflow tract (LVOT) obstruction, and other potential procedure pitfalls. Results of 3D prototyping were then compared to post procedural imaging to determine how closely the achieved procedural result mirrored the 3D modeled result.Results3D prototyping simulated LVOT obstruction in one patient who developed it and in another patient who underwent alcohol septal ablation prior to TMVR. Valve sizing correlated with actual placed valve size in six out of the eight patients and more than mild paravalvular leak (PVL) was simulated in two of the three patients who had it. Patients who had mismatch between their modeled valve size and post‐procedural imaging were the ones that had anterior leaflet resection which could have altered valve sizing and PVL simulation. 3D printed model of one of the latter patients allowed modification of anterior leaflet to simulate surgical resection and was able to estimate the size and location of the PVL after inserting a valve stent into the physical model.Conclusion3D prototyping in TMVR for severe MAC is feasible for simulating valve sizing, apposition, expansion, PVL, and LVOT obstruction.

Background Mitral regurgitation is a heterogeneous disease. Determining which patients derive optimal outcomes from transcatheter edge‐to‐edge mitral valve repair (TMVR) remains challenging. We sought to determine whether baseline mitral valve anatomic characteristics are predictive of left atrial pressure (LAP) changes during TMVR with MitraClip. Methods and Results Consecutive patients with severe mitral regurgitation undergoing TMVR (n=112) underwent continuous intraprocedural LAP monitoring and retrospective echocardiographic analysis for specific mitral anatomic characteristics. Procedural success (optimal LAP reduction) was defined as ≥40% reduction in left atrial V‐wave pressure compared with baseline. Echocardiographic predictors of optimal LAP reduction and increased postprocedure mean diastolic gradient were evaluated. Mean age was 79±14 years, and 36 patients (32%) were women. Primary, mixed, and secondary mitral regurgitation were present in 78 patients (70%), 22 patients (20%), and 12 patients (10%), respectively. Baseline mean LAP and V‐wave were 22±6 and 38±13 mm Hg; after TMVR, these decreased to 19±5 and 27±10 mm Hg, respectively ( P <0.0001 for both). Independent predictors of optimal LAP reduction were the presence of a flail scallop, mitral regurgitation localized to a single scallop, and high‐quality 3‐dimensional echocardiographic imaging. Independent predictors of elevated postprocedure mean diastolic gradient were elevated preprocedure mean diastolic gradient, mitral annular calcification, and implantation of multiple clips. Conclusions Mitral valve pathoanatomic features, including a flail leaflet and single jet, are predictive of optimal LAP reduction with TMVR. High‐quality 3‐dimensional imaging may help select patients with the highest likelihood of optimal hemodynamic results with TMVR. These data expand current knowledge about patient selection for TMVR and deserve further study in larger cohorts.

Background— Percutaneous closure of prosthetic mitral valve paravalvular leak (PVL) has emerged as an alternative to surgical treatment in high-risk patients. Limited data exist on the impact of successful percutaneous PVL closure on midterm outcomes. Methods and Results— We examined consecutive patients who underwent percutaneous mitral PVL closure at Mayo Clinic, Rochester, MN, between January 2006 and January 2017. Procedural success, in-hospital outcomes, and midterm mortality were assessed. A total of 231 patients underwent percutaneous mitral PVL repair at a mean age of 67±12 years. Mean time from mitral valve replacement to percutaneous PVL repair was 1.25 (0.31–7.25) years. One hundred sixty-two patients (70%) had ≤mild PVL after the procedure. Compared with those who had >mild residual PVL, patients with ≤mild residual PVL had lower rates of repeat surgical interventions (6% versus 17%; P =0.004) and lower all-cause mortality at 30 days (1% versus 14%; P <0.001) and 1 year (15% versus 39%; P <0.001). Survival at 3 years was 61% in patients who had ≤mild residual leak and 47% in patients with higher grade of residual PVL ( P =0.002). Conclusions— In a large consecutive cohort of patients undergoing percutaneous mitral PVL closure, successful percutaneous reduction of the PVL to mild or less was associated with significant midterm survival benefit.

AbstractObjectiveThe objective of this study was to determine the accuracy of left atrial pressure (LAP) measurement through the manufacturer provided steerable guiding catheter (SGC) during transcatheter mitral valve repair (TMVR).BackgroundLAP measurement during TMVR has been shown to be associated with clinical improvement when measured through a dedicated catheter.MethodsSimultaneous LAP was performed in consecutive patients using an independent fluid‐filled 4F multipurpose catheter and compared to LAP waveforms measured through the manufacturer‐provided MitraClip SGC during TMVR (Abbott, Santa Clara, CA).ResultsMean age of 10 consecutive subjects with primary mitral regurgitation undergoing TMVR was 83 ± 3 years (60% female). Left atrial v wave and mean pressures through the dedicated catheter were 42 ± 7 and 24 ± 3 mmHg vs. 35 ± 7 and 23 ± 3 mmHg through the SGC (P < 0.001 and P = 0.23, respectively). Mean differences in v wave and mean LAP were 8 ± 4 and 1.0 ± 2.4 mmHg (percent difference 19 and 3%), respectively. SGC waveform overdamping was observed in all cases.ConclusionsLeft atrial v wave pressure measurement through a dedicated catheter with sideholes during TMVR has superior accuracy compared to the manufacturer provided SGC, which results in waveform overdamping and a significant underestimation of v wave pressure. These data have important implications for clinical practice.

AbstractBackgroundThere are sparse clinical data on the procedural trends, outcomes and readmission rates following FDA approval and expansion of Transcatheter mitral valve repair/MitraClip®. Whether a complex new technology can be disseminated safely and quickly is controversial.MethodsThe study cohort was derived from the National Readmission Data (NRD) 2013–14. MitraClip® was identified using appropriate International Classification of Diseases, 9th Revision, Clinical Modification (ICD‐9‐CM) codes. The primary outcome was a composite of in‐hospital mortality + procedural complications. Secondary outcome included 30‐day readmissions. Hierarchical two level logistic models were used to evaluate study outcomes.ResultsOur analysis included 2003 MitraClip® procedures. Overall in‐hospital mortality was 3.9%. As expected, there was a significant increase in procedural volume post‐FDA approval. Importantly, a corresponding downward trend in mortality and procedural complications was observed. Significant predictors of in‐hospital mortality and procedural complications included the use of vasopressors (P <0.001) and hemodynamic support (P < 0.001). Higher hospital volume (≥10 MitraClips/year) was associated with lower in‐hospital mortality and complications (P = 0.02). There were 304 (15.1%) 30‐day readmissions, with heart failure being the most common cause of readmission. Elective procedures had lower in‐hospital mortality (P < 0.001) and lower readmission rates (P = 0.011) compared with nonelective procedures.ConclusionA significant increase in MitraClip® procedural volumes occurred post‐FDA approval. Overall morbidity and mortality were low and trended downwards. Hospital procedure volume ≥10 cases were associated with lower mortality and overall complication rates. These data suggest a successful roll out of a very complex novel structural heart procedure.

Structural heart disease is a rapidly evolving field, and approaches to procedural training are not standardized. We describe a novel modular approach to procedural training that considers each procedure as a series of building blocks that may be taught and assessed separately. Ten key structural heart disease building blocks can be identified, which, when combined with the cognitive skills of structural intervention and device-specific training, allow appropriate planning and implementation of structural procedures. Structural procedures require careful navigation of the aorta, left atrium, and right heart, including detailed understanding of relational anatomy. Component blocks include large bore vascular access, navigation within the left atrium, occlusion, snaring, and 3-dimensional relational anatomy. These building blocks also provide the foundation for new procedures through innovative use of the skill sets and devices to approach new clinical problems. The addition of device-specific training may be provided via proctoring and industry support. Using this approach, competency in less common procedures may be achieved and maintained. We discuss each building block in detail, approaches specific to the structural heart disease patient, the need for cross-discipline training, and empirical recommendations for training using this approach. We postulate that this new paradigm may be the preferred approach for training and assessment of structural heart disease interventional skills.

Background Studies assessing the differential impact of sex on outcomes of aortic valve replacement ( AVR ) yielded conflicting results. We sought to investigate sex‐related differences in AVR utilization, patient risk profile, and in‐hospital outcomes using the Nationwide Inpatient Sample. Methods and Results In total, 166 809 patients (63% male and 37% female) who underwent AVR between 2003 and 2014 were identified, and 48.5% had a concomitant cardiac surgery procedure. Compared with men, women were older and had more nonatherosclerotic comorbid conditions including hypertension, diabetes mellitus, obstructive pulmonary disease, atrial fibrillation/flutter, and anemia but fewer incidences of coronary and peripheral arterial disease and prior sternotomies. In‐hospital mortality was significantly higher in women (5.6% versus 4%, P <0.001). Propensity matching was performed to assess the impact of sex on the outcomes of isolated AVR and yielded 28 237 matched pairs of male and female participants. In the propensity‐matched groups, in‐hospital mortality was higher in women (3.3% versus 2.9%, P <0.001). Along with vascular complications and blood transfusion (6% versus 5.6%, P =0.027 and 40.4% versus 33.9%, P <0.001, respectively). Rates of stroke, permanent pacemaker implantation, and acute kidney injury requiring dialysis were similar (2.4% versus 2.4%, P =0.99; 6% versus 6.3%, P =0.15; and 1.4% versus 1.3%, P =0.14, respectively). Length of stay median and interquartile range were both similar between groups (7±6 days). Rates of nonhome discharge were higher among women (27.9% versus 19.6%, P <0.001). Conclusions Women have worse in‐hospital mortality following AVR compared with men. Coupled with the accumulating evidence suggesting higher magnitude of benefit of transcatheter AVR over AVR in women, women should perhaps be offered transcatheter AVR over AVR at a lower threshold than men.

AbstractObjectivesTo investigate the feasibility, procedural success, and outcomes of paravalvular leak (PVL) closure in patients with prior transcatheter aortic valve replacement (TAVR).BackgroundPVL after TAVR is associated with adverse patient outcomes and increased mortality. Percutaneous PVL closure has emerged as a therapeutic strategy for addressing this issue, but data for transcatheter PVL repair after TAVR remains limited.MethodsThis is a single center retrospective review of PVL closure after TAVR. Patients with balloon‐expandable or self‐expanding prostheses were included. Baseline patient demographics, procedural characteristics, complications, and clinical outcomes were reviewed.ResultsA total of 18 patients with clinically significant PVL after TAVR referred for PVL closure were identified during the study period. Procedural success resulting in successful transcatheter occluder plug delivery was 78% (14 cases). Balloon postdilatation (2/4) and valve‐in‐valve (2/4) were used effectively in the remaining patients after an unsuccessful PVL closure attempt. PVL grading by echocardiography decreased from moderate or severe to < moderate in 13 patients (72%). Adverse events including cardiac tamponade and acute kidney injury occurred in 1 case each. One‐month all‐cause mortality was 11%.ConclusionIn selected patients, percutaneous PVL repair following TAVR is feasible and effective for both balloon‐expandable and self‐expanding prostheses. Most patients undergoing PVL closure after TAVR require a single occluder plug placement for reduction in PVL to mild or less.

AbstractBackgroundData on the clinical utility of left atrial (LA) hemodynamic monitoring during percutaneous mitral interventions are limited.ObjectivesTo evaluate the association between intraprocedural LA pressures during percutaneous mitral paravalvular leak (PVL) closure and long term survival.MethodsPatients who underwent mitral PVL repair with invasive LA pressure monitoring were divided at baseline to three tertiles based on their mean final LA pressure (<25%; 25‐30%; >30% of mean systolic blood pressure). Primary outcome was all‐cause mortality.Results134 patients (mean age 68 ± 12 years) were studied. Over 3 year mean follow‐up, 81 (38%) patients died. The cumulative probability of death at 3 years was significantly higher among patients in the highest LA pressure tertile (56 ± 8% vs. 28 ± 5%, log rank P < 0.001). More than mild residual mitral regurgitation (MR) by transesophageal echocardiography (TEE) was associated with a 2.5‐fold increased risk of death and patients in the highest LA pressure tertile had 2.2‐fold higher mortality (P < 0.001 and = 0.003 respectively). After adjustment for residual MR by TEE, each 10% acute procedural reduction in LA pressures was associated with a significant 9% reduced risk of death (P = 0.023). Multivariate Cox regression with adjustment for multiple predictors of death showed that patients in lower LA pressure tertiles had 59% lower mortality (P = 0.003).ConclusionLower LA pressure following mitral PVL closure is an independent predictor of improved survival, even after adjustment for residual MR. LA pressure monitoring may be a useful tool for procedural guidance during mitral PVL closure.