Rest and Stress Longitudinal Systolic Left Ventricular Mechanics in Hypertrophic Cardiomyopathy: Implications for Prognostication

Iraklis Pozios, Aurelio Pinheiro, Celia Corona-Villalobos, Lars L. Sorensen, Zeina Dardari, Hong yun Liu, Kenneth Cresswell, Susan Phillip, David Alan Bluemke, Stefan L. Zimmerman, Roselle Abraham, Theodore Abraham

Research output: Contribution to journalArticle

Abstract

Background: Exercise intolerance is the most common symptom in hypertrophic cardiomyopathy (HCM). We examined whether inability to augment myocardial mechanics during exercise would influence functional performance and clinical outcomes in HCM. Methods: Ninety-five HCM patients (32 nonobstructive, 32 labile-obstructive, 31 obstructive) and 26 controls of similar age and gender distribution were recruited prospectively. They underwent rest and treadmill stress strain echocardiography, and 61 of them underwent magnetic resonance imaging. Mechanical reserve (MRES) was defined as percent change in systolic strain rate (SR) immediately postexercise. Results: Global strain and SR were significantly lower in HCM patients at rest (strain: nonobstructive, −15.6 ± 3.0; labile-obstructive, −15.9 ± 3.0; obstructive, −13.8 ± 2.9; control, −17.7% ± 2.1%, P < .001; SR: nonobstructive, −0.92 ± 0.20; labile−obstructive, −0.94 ± 0.17; obstructive, −0.85 ± 0.18; control, −1.04 ± 0.14 s−1, P = .002); and immediately postexercise (strain: nonobstructive, −15.6 ± 3.0; labile-obstructive, −17.6 ± 3.6; obstructive, −15.6 ± 3.6; control, −19.2 ± 3.1%; P = .001; SR: nonobstructive, −1.41 ± 0.37; labile-obstructive, −1.64 ± 0.38; obstructive, −1.32 ± 0.29; control, −1.82 ± 0.29 s−1, P < .001). MRES was lower in nonobstructive and obstructive compared with labile-obstructive and controls (51% ± 29%, 54% ± 31%, 78% ± 38%, 77% ± 30%, P = .001, respectively). Postexercise SR and MRES were associated with exercise capacity (r = 0.47 and 0.42, P < .001 both, respectively). When adjusted for age, gender, body mass index, E/e’, and resting peak instantaneous systolic gradient, postexercise SR best predicted exercise capacity (r = 0.74, P = .003). Postexercise SR was correlated with extent of late gadolinium enhancement (r = 0.34, P = .03). By Cox regression, exercise SR and MRES predicted ventricular tachycardia/ventricular fibrillation (VT/VF) even after adjustment for age, gender, family history of sudden cardiac death, septum ≥ 3 cm and abnormal blood pressure response (P = .04 and P = .046, respectively). Conclusions: Nonobstructive and obstructive patients have reduced MRES compared with labile-obstructive and controls. Postexercise SR correlates with LGE and exercise capacity. Exercise SR and MRES predict VT/VF.

Original languageEnglish (US)
JournalJournal of the American Society of Echocardiography
DOIs
StateAccepted/In press - Jan 1 2018

Keywords

  • Arrhythmia
  • Exercise echocardiography
  • Hypertrophic cardiomyopathy
  • Mechanics

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Cardiology and Cardiovascular Medicine

Fingerprint Dive into the research topics of 'Rest and Stress Longitudinal Systolic Left Ventricular Mechanics in Hypertrophic Cardiomyopathy: Implications for Prognostication'. Together they form a unique fingerprint.

Cite this