Ciampi, Q C Quirino

Abstract Introduction Transthoracic echocardiography (TTE) identifies a hypercontractile phenotype (HP) in chronic coronary syndromes (CCS), characterized by elevated resting left ventricular (LV) elastance (force = systolic blood pressure/end-systolic volume). To evaluate the prognostic significance and functional correlates of HP. Methods In a prospective multicentre study, 10 677 patients with CCS underwent resting TTE to assess LV ejection fraction (EF), stroke volume, and force by quantitative volumetric echocardiography. All patients were followed for the endpoint of all-cause mortality. In a subset of 5834 patients, stress echocardiography (exercise or dobutamine) was performed for LV contractile reserve and heart rate reserve. Results Patients were stratified into Force quintiles (Q1–Q5). Patients with hypercontractile phenotype exhibited lower stroke volume at rest (Q5 = 34.8 ± 12.3 vs Q1–Q4 = 57.4 ± 19.1 mL; P < .01) and higher EF at rest (Q5 = 64.8 ± 6.9% vs Q1–Q4 = 58.1 ± 8.7%, P < .01). During a median follow-up of 24 months (interquartile range = 12–40 months), 509 deaths occurred. The exposure-adjusted death rate was lowest in Q3 (3.53–4.51 mmHg/mL; 1.03 per 100 person/years) and higher in Q1 (≤2.62 mmHg/mL, 2.88), Q2 (2.63–3.52 mmHg/mL, 1.86), Q4 (4.52–6.11 mmHg/mL, 1.56), and Q5 (HP, >6.11 mmHg/mL; 1.88; P < .0001 vs Q1 and Q3). Multivariable analysis identified HP (Q5; HR 1.531 vs Q3, 95% CI 1.116–2.099; P = .006) and EF (HR 0.963, 95% CI 0.953–0.972; P < .0001) as independent predictors of death. During exercise or dobutamine stress, HP showed reduced LV contractile reserve (ΔEF: Q5 = 4.3 ± 9.4% vs Q1–Q4 = 7.0 ± 9.3%; P < .001) and blunted heart rate reserve (Q5 = 1.77 ± 0.33 vs Q1–Q4 = 1.85 ± 0.39; P < .01). All patients with force-based LV contractile reserve >4.1 (present in 185, 3.2% of the population) survived. Conclusion Patients with CCS with HP assessed by resting TTE demonstrate higher mortality and multilayered functional impairment, including reduced LV contractile and chronotropic reserves. Hypercontractile phenotype improved the prediction of mortality by EF. A ‘stronger’ heart is, in fact, functionally and prognostically weaker.

Abstract Background Inducible ST-segment depression during stress echocardiography (SE) is associated with a higher risk in patients with inducible regional wall motion abnormality (RWMA). Objective To assess ST segment elevation's prevalence and functional correlates during SE. Methods ECG response was analyzed in 1712 patients (age 63±12 years; 1011 men, 59%) undergoing SE for chronic coronary syndromes (CCS) prospectively recruited at 39 laboratories. Among the patients analyzed, 1286 (75%) performed SE with exercise, 306 (18%) with dobutamine and 120 (7%) with a vasodilator. ECG response was considered abnormal in case of ST-segment shift >1.0 mm from baseline at 80 ms from the J point developed in ≥2 contiguous leads during SE. The stress to rest (∆) change in the wall motion score index (WMSI) was assessed in all patients. Coronary angiography was available in 765 patients. Major adverse cardiac events (MACE) were the outcome measure in 746 patients with follow-up information. Results No significant ST segment shift was observed in 1000 patients (58%, Group 1), ST-segment depression occurred in 609 patients (35.5%, Group 2), and ST-segment elevation in 103 patients (6%, Group 3). ST-segment elevation occurred in 66/1286 patients (5.2%) with exercise, 30/306 with dobutamine (10%), and 7/120 with vasodilators (6%, p = ns vs. exercise and p<0.01 vs. dobutamine). The prevalence of stress-induced RMWA was higher in Group 2 (38.1%) compared to Group 3 (33%) and Group 1 (11.9%. P< 0.001 vs. Groups 2 and 3); however, the ΔWMSI was more pronounced in Group 3 compared to Group 2 and Group 1 (p = ns vs. Group 2 and p<0.001 vs. Group 1). (Figure, left panel). Non-significant CAD (defined as coronary stenosis <50% on coronary angiography) was more prevalent in Group 1 (36%) and 3 (40%) compared to Group 2 (17.5%, p<0.01 vs. Group 1 and 3). . During a median follow-up of 387 days (IQ range 314-603 days), 150 events occurred in 112 patients: 14 all-cause deaths, 39 acute myocardial infarctions, 19 atrial fibrillations, 34 late coronary revascularizations, and 44 acute heart failure hospitalizations. The exposure-adjusted event rate was the lowest in Group 1 compared to Groups 2 and 3 (Figure, right panel). Conclusion In all-comers with CCS, the electrocardiographic pattern of ST-segment elevation is not rare, more frequent with dobutamine, associated with more stress-to-rest change in RWMA and more events despite less extensive underlying anatomic CAD. The paradox of more ischemia with less coronary stenosis is consistent with a coronary vasospastic origin as an important yet frequently overlooked cause of stress-induced ST segment elevation.Figure