Nkomo, Vuyisile T.

AbstractBackgroundQRS fragmentation (fQRS) during baseline ventricular conduction, a myocardial fibrosis marker, is associated with increased risk of ventricular tachyarrhythmias but may not manifest unless ventricular activation change is provoked. We examined the association of fQRS during right ventricular (RV) pacing with death and ventricular tachyarrhythmia in patients with left ventricular (LV) dysfunction undergoing electrophysiology study (EPS).Methods and resultsStudy participants had LV dysfunction (ejection fraction < 50%) undergoing EPS from January 2002 to May 2014 at Mayo Clinic in Rochester, Minnesota. fQRS during RV stimulation involved >2 notches on R/S waves identified in ≥2 contiguous standard electrocardiographic leads representing anterior, inferior, or lateral ventricular segments. Primary outcomes were ventricular tachyarrhythmias that were symptomatic or required intervention and total and cardiac deaths. In all, 528 patients participated (mean age, 65 years; male sex, 80%). Of them, 312 (59%) had ischemic cardiomyopathy and mean (SD) left ventricular ejection fraction (LVEF) of 33.2% (9.5%); 457 (87%) had implantable cardiac devices (implanted defibrillator, n = 380). Mean (SD) follow‐up was 3.2 (3.0) years. fQRS during RV pacing was observed in 292 patients (60%) in any ventricular segment. Patients with fQRS during RV pacing had 2.5 higher rate of ventricular tachyarrhythmia events than patients with no fQRS (hazard ratio [95% CI], 2.45 [1.5–4.2]; P < 0.01), after correcting for baseline ventricular conduction defect and QRS duration, LVEF, inducible sustained ventricular tachycardia, diabetes mellitus, chronic kidney disease, and ischemic cardiomyopathy.ConclusionsRV stimulation can unmask fQRS, and it is associated with increased risk of ventricular tachyarrhythmia in LV dysfunction.

Background: Echocardiographic quantitation of degenerative mitral regurgitation (DMR) is recommended whenever possible in clinical guidelines but is criticized and its scalability to routine clinical practice doubted. We hypothesized that echocardiographic DMR quantitation, performed in routine clinical practice by multiple practitioners, predicts independently long-term survival and thus is essential to DMR management. Methods: We included patients diagnosed with isolated mitral valve prolapse from 2003 to 2011 and any degree of mitral regurgitation quantified by any physician/sonographer in routine clinical practice. Clinical/echocardiographic data acquired at diagnosis were retrieved electronically. The end point was mortality under medical treatment analyzed by Kaplan-Meier method and proportional hazard models. Results: The cohort included 3914 patients (55% male) mean age (±standard deviation) 62±17 years with left ventricular ejection fraction 63±8% and median after routinely-measured effective regurgitant orifice area (EROA) [interquartile range], 19 [0–40] mm 2 . During follow-up (6.7±3.1 years), 696 patients died under medical management, and 1263 underwent mitral surgery. In multivariate analysis, routinely-measured EROA was associated with mortality (adjusted hazard ratio, 1.19; 95% confidence interval, 1.13–1.24; P <0.0001 per 10 mm 2 ) independently of left ventricular ejection fraction and end-systolic diameter, symptoms, and age/comorbidities. The association between routinely-measured EROA and mortality persisted with competitive risk modeling (adjusted hazard ratio, 1.15; 95% confidence interval, 1.10–1.20; P <0.0001 per 10 mm 2 ), or in patients without guideline-based class I/II surgical triggers (adjusted hazard ratio, 1.19; 95% confidence interval, 1.10–1.28; P <0.0001 per 10 mm 2 ) and in all subgroups examined (all P <0.01). Spline curve analysis showed that, compared with general population mortality, excess mortality appears for moderate DMR (EROA ≥20 mm 2 ), becomes notable at EROA ≥30 mm 2 , and steadily increases with higher EROA levels (eg, higher EROA levels beyond the 40 mm 2 threshold). Conclusions: Echocardiographic DMR quantitation is scalable to routine practice and is independently associated with clinical outcome. Routinely-measured EROA is strongly associated with long-term survival under medical treatment. Excess mortality versus the general population appears in the moderate DMR range and steadily increases with higher EROA. Hence, individual EROA values should be integrated into therapeutic considerations, in addition to categorical DMR grading.

Grading severity of AS in AF is complicated by varying stroke volumes associated with fluctuating maximum velocities and pressure gradients across the aortic valve. Current guidelines recommend averaging five continuous‐wave peak velocity and mean gradient (MG) Doppler signals across the aortic valve when estimating severity of AS in AF. However, it is unknown when grading severity of AS how the average of multiple Doppler signals vs the highest Doppler signal in AF compares to the Doppler signals when the patient is in normal sinus rhythm. We present a series of patients with AS who had two echocardiograms performed within 2‐4 months of each other, one when in normal sinus rhythm and one when in AF, and compare the aortic valve hemodynamics associated with the two rhythms.

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.

Background— It is presumed that echocardiographic laboratory accreditation leads to improved quality, but there are few data. We sought to compare the quality of echocardiographic examinations performed at accredited versus nonaccredited laboratories for the evaluation of valvular heart disease. Methods and Results— We enrolled 335 consecutive valvular heart disease subjects who underwent echocardiography at our institution and an external accredited or nonaccredited institution within 6 months. Completeness and quality of echocardiographic reports and images were assessed by investigators blinded to the external laboratory accreditation status and echocardiographic results. Compared with nonaccredited laboratories, accredited sites more frequently reported patient sex (94% versus 78%; P <0.001), height and weight (96% versus 63%; P <0.001), blood pressure (86% versus 39%; P <0.001), left ventricular size (96% versus 83%; P <0.001), right ventricular size (94% versus 80%; P =0.001), and right ventricular function (87% versus 73%; P =0.006). Accredited laboratories had higher rates of complete and diagnostic color (58% versus 35%; P =0.002) and spectral Doppler imaging (45% versus 21%; P <0.0001). Concordance between external and internal grading of external studies was improved when diagnostic quantification was performed (85% versus 69%; P =0.003), and in patients with mitral regurgitation, reproducibility was improved with higher quality color Doppler imaging. Conclusions— Accredited echocardiographic laboratories had more complete reporting and better image quality, while echocardiographic quantification and color Doppler image quality were associated with improved concordance in grading valvular heart disease. Future quality improvement initiatives should highlight the importance of high-quality color Doppler imaging and echocardiographic quantification to improve the accuracy, reproducibility, and quality of echocardiographic studies for valvular heart disease.