Maureen Martin

Outcome of patients with hypertrophic obstructive cardiomyopathy after percutaneous transluminal septal myocardial ablation and septal myectomy surgery.

OBJECTIVES This study was conducted to evaluate follow-up results in patients with hypertrophic obstructive cardiomyopathy (HOCM) who underwent either percutaneous transluminal septal myocardial ablation (PTSMA) or septal myectomy. BACKGROUND Controversy exists with regard to these two forms of treatment for patients with HOCM. METHODS Of 51 patients with HOCM treated, 25 were treated by PTSMA and 26 patients via myectomy. Two-dimensional echocardiograms were performed before both procedures, immediately afterwards and at a three-month follow-up. The New York Heart Association (NYHA) functional class was obtained before the procedures and at follow-up. RESULTS Interventricular septal thickness was significantly reduced at follow-up in both groups (2.3 +/- 0.4 cm vs. 1.9 +/- 0.4 cm for septal ablation and 2.4 +/- 0.6 cm vs. 1.7 +/- 0.2 cm for myectomy, both p < 0.001). Estimated by continuous-wave Doppler, the resting pressure gradient (PG) across the left ventricular outflow tract (LVOT) significantly decreased immediately after the procedures in both groups (64 +/- 39 mm Hg vs. 28 +/- 29 mm Hg for PTSMA, 62 +/- 43 mm Hg vs. 7 +/- 7 mm Hg for myectomy, both p < 0.0001). At three-month follow-up, the resting PG remained lower in the PTSMA and myectomy groups (24 +/- 19 mm Hg and 11 +/- 6 mm Hg, respectively, vs. those before procedures, both p < 0.0001). The NYHA functional class was also significantly improved in both groups (3.5 +/- 0.5 vs. 1.9 +/- 0.7 for PTSMA, 3.3 +/- 0.5 vs. 1.5 +/- 0.7 for myectomy, both p < 0.0001). CONCLUSIONS Both myectomy and PTSMA reduce LVOT obstruction and significantly improve NYHA functional class in patients with HOCM. However, there are benefits and drawbacks for each therapeutic method that must be counterbalanced when deciding on treatment for LVOT obstruction.

Right atrial volume index in chronic systolic heart failure and prognosis.

OBJECTIVES The aim of this study was to determine the relationship between right atrial volume index (RAVI) and right ventricular (RV) systolic and diastolic function, as well as long-term prognosis in patients with chronic systolic heart failure (HF). BACKGROUND RV dysfunction is associated with poor prognosis in patients with HF, although echocardiographic assessment of RV systolic and diastolic dysfunction is challenging. The ability to visualize the RA allows a quantitative, highly reproducible assessment of the RA volume that can be indexed to body surface area. METHODS The ADEPT (Assessment of Doppler Echocardiography for Prognosis and Therapy) trial enrolled 192 subjects with chronic systolic HF (left ventricular ejection fraction [LVEF] <or=35%). The RA volume was calculated by Simpsons method using single-plane RA area and indexed to body surface area (RAVI). RV systolic function was graded as normal, mild, mild-moderate, moderate, moderately severe, or severe dysfunction. RESULTS In our study cohort, the mean RAVI was 28 +/- 15 ml/m(2), and increased with worsening RV systolic dysfunction, LVEF, and LV diastolic dysfunction (Spearmans r = 0.61, r = 0.26, and r = 0.51, respectively; p < 0.001 for all). RAVI correlated modestly with echocardiographic estimates of RV diastolic dysfunction, including tricuspid early/late velocities ratio (Spearmans r = 0.34, p < 0.0001), hepatic vein systolic/diastolic ratio (Spearmans r = -0.26, p < 0.001) but not tricuspid early/tricuspid annular early velocities ratio (E/Ea) (Spearmans r = 0.12, p = 0.11). Increasing tertiles of RAVI were predictive of death, transplant, and/or HF hospitalization (log-rank p = 0.0002) and remained an independent predictor of adverse clinical events after adjusting for age, B-type natriuretic peptide, LV ejection fraction, RV systolic dysfunction, and tricuspid E/Ea ratio (hazard ratio: 2.00, 95% confidence interval: 1.15 to 3.58, p = 0.013). CONCLUSIONS In patients with chronic systolic HF, RAVI is a determinant of right-sided systolic dysfunction. This quantitative and reproducible echocardiographic marker provides independent risk prediction of long-term adverse clinical events.

Comparison of left ventricular diastolic function in obstructive hypertrophic cardiomyopathy in patients undergoing percutaneous septal alcohol ablation versus surgical myotomy/myectomy

Both percutaneous transcoronary alcohol septal reduction (ASR) and surgical myectomy are effective treatments to relieve left ventricular (LV) outflow tract obstruction in obstructive hypertrophic cardiomyopathy (HC). LV diastolic function was assessed by echocardiography in 57 patients with obstructive HC at baseline and 5 +/- 4 months after ASR (n = 37) or surgical myectomy (n = 20). LV outflow tract pressure gradient decreased from 65 +/- 40 to 23 +/- 21 mm Hg (p <0.01) after treatment. The ratio of the early-to-late peak diastolic LV inflow velocities, and the ratio of the early peak diastolic LV inflow velocity to the lateral mitral annulus early diastolic velocity determined by tissue Doppler imaging significantly decreased after the procedures (1.6 +/- 1.7 vs 1.0 +/- 0.7 and 15 +/- 8 vs 11 +/- 5, respectively), whereas LV inflow propagation velocity significantly increased (60 +/- 24 vs 71 +/- 36 cm/s). Left atrial size decreased from 29 +/- 7 to 25 +/- 6 cm(2) (p <0.05). Patients had a significant improvement in New York Heart Association functional class and in exercise performance. When comparing ASR with myectomy, no difference was found in the degree of change in any parameter of diastolic function. Thus, diastolic function indexes obtained by echocardiography changed after septal reduction interventions in patients with obstructive HC; this change was similar to that after surgical myectomy and ASR.

Clinical Significance of Endogenous Vasoactive Neurohormones in Chronic Systolic Heart Failure

BACKGROUND Neurohormonal activation is a pathophysiological hallmark of acute and chronic heart failure (HF). The clinical significance of more recently discovered endogenous vasoactive hormones has not been well-characterized. METHODS AND RESULTS In 154 subjects with stable, chronic systolic HF (New York Heart Association Class I-IV, left ventricular [LV] ejection fraction <or=40%), we measured plasma levels of urocortin 1 (UCN-1), urotensin II (UT-II), and endothelin-1 (ET-1) and performed comprehensive echocardiography with assessment of cardiac structure and performance. Adverse clinical events (all-cause mortality, cardiac transplantation or HF hospitalization) were prospectively tracked for a median of 39 months. Plasma levels of UCN-1 and ET-1 (but not UT-II) increased with LV diastolic dysfunction stage, right ventricular systolic dysfunction class, and mitral regurgitation severity (P < .01 for all). Higher plasma levels of UCN-1 and ET-1 (but not UT-II) predicted increased risk for adverse clinical events. After adjustment for age, LV ejection fraction, and plasma amino-terminal pro-B-type natriuretic peptide, plasma UCN-1 >or=12.1 pM (HR: 2.02, 95% CI: 1.08-3.93, P = .029) and ET-1 >or=2.29 pM (HR: 2.52, 95% CI: 1.24-5.03, P = .011) remained significant independent risk factors for adverse clinical events. CONCLUSION Higher levels of plasma levels of UCN-1 and ET-1 but not UT-II were associated with worse LV diastolic performance and poorer long-term clinical outcomes in patients with chronic systolic HF.

Relation of mechanical dyssynchrony with underlying cardiac structure and performance in chronic systolic heart failure: implications on clinical response to cardiac resynchronization

AIMS The aim of this study is to describe the relationship between ventricular mechanical dyssynchrony (VMD) and echocardiographic indices of cardiac remodelling. METHODS AND RESULTS We evaluated 219 ambulatory patients with chronic systolic heart failure [left ventricular ejection fraction (LVEF) <or= 35%, New York Heart Association functional classes II-IV] who underwent echocardiographic evaluation. The presence of dyssynchrony was defined by Bader criteria (intra-VMD > 40 ms and/or inter-VMD > 38 ms). In our study cohort, 59% of patients had evidence of dyssynchrony (including 44% with intra-VMD and 38% with inter-VMD, and 20% with both). Inter-VMD correlated with QRS width (r = 0.48, P < 0.0001) better than intra-VMD (r = 0.24, P < 0.001). Higher inter-VMD was associated with less restrictive filling patterns (rank sums P = 0.012) and larger left ventricular end-diastolic dimension (LVEDD, rank sums P = 0.020), but intra-VMD values were similar across diastolic stages and LVEDD tertiles. CONCLUSION In chronic systolic heart failure, evidence of mechanical dyssynchrony is prevalent but the underlying cardiac structure and performance may influence the degree of inter-VMD more so than intra-VMD. Our data suggest that the extent of inter-VMD is directly related to the degree of dilatation of the heart but inversely to diastolic dysfunction.

Acute Reduction of Functional Mitral Regurgitation in Canine Model Using an Epicardial Device

PURPOSE This study evaluated the short-term feasibility of a novel epicardial device that treats functional mitral regurgitation by simultaneously changing the mitral and the left ventricular geometry. DESCRIPTION We implanted a prototype device that consists of 2 tissue anchors, a deflector, and a flexible tightening chord in 7 mongrel dogs with heart failure and functional mitral regurgitation induced by rapid ventricular pacing. Hemodynamic and echocardiographic data were obtained before and after device implantation. EVALUATION The device acutely reduced the mitral regurgitation grade from 3.2 +/- 0.3 to 0.9 +/- 0.5 (p < 0.001). Left ventricular end-diastolic volume (79.6 +/- 23.6 to 61.2 +/- 16.9 mL; p = 0.004) and end-systolic volume (63.1 +/- 17.3 to 49.2 +/- 12.3 mL; p = 0.006) decreased substantially. End-systolic elastance significantly increased from 1.9 +/- 1.0 to 2.6 +/- 1.4 mm Hg/mL (p = 0.02). Device implantation did not alter coronary perfusion. CONCLUSIONS The epicardial device acutely reduced functional mitral regurgitation and improved left ventricular geometry. Further studies are required to demonstrate the long-term safety and efficacy of this concept.