Background: A hypercontractile heart is defined as a left ventricle (LV) with excessively increased systolic function and a high ejection fraction. Does this also entail good diastolic function? We looked at the diastolic / relaxation properties of subjects with a hypercontractile heart.
Methods: Consecutive echocardiography examinations in a hospital laboratory during 5 years were divided into examinations with a normal versus hypercontractile systolic LV function based on qualitative assessment. All exams with abnormal systolic function, significant LV hypertrophy (intra-ventricular septal thickness≥15mm) or valve disease were excluded.
Results: A total of 19,378 exams were evaluated. 1,167 exams (5.7%) were with hypercontractile systolic function. Exams with a hypercontractile systolic function were of older subjects (68±15 vs. 56±20 years, P<0.001) with a higher proportion of females (61% vs 49%, P<0.001). Mean ejection fraction (EF) was higher (72±7 vs. 64±8%, P<0.001). LV size was smaller: LV end-diastolic diameter (46±6 vs. 49±5 mm, P<0.001), LV end-systolic diameter (25±5 vs. 30±5, P<0.001) and LV mass index was higher (95±30 vs. 85±27 g/m2, P<0.001). E to A ratio was lower (0.9±0.5 vs. 1.2±0.6, P<0.001) Relaxation was reduced as evident by a smaller lateral e prime (8.4±4.6 vs 11±6 cm/s, P<0.001) with the majority of exams having an abnormal e prime (<10 cm/s): 74% vs 39%, P<0.001). Deceleration time was longer (230±76 vs. 198±95, P<0.001) and left atrial volume index was larger (29±11 vs. 25±13 mL/m2, P<0.001). Peak tricuspid regurgitation gradient was also higher (33±13 vs. 26±11, P<0.001). Moreover, LV end-diastolic pressures were higher as evident by a higher e to e prime ratio (11±5 vs. 8.1±4.4, P<0.001). Propensity score matching of hypercontractile to normal LV function exams adjusting for age and gender demonstrated essentially the same findings. Sensitivity analysis based on an EF cutoff (Normal EF<70%, hypercontractile EF≥70%) demonstrated identical findings.
Conclusions: Subjects with a hypercontractile systolic function have impaired LV relaxation and increased LV diastolic pressures. A hypercontractile heart apparently is not a 'super-normal' functioning heart.
