Factors contributing to energy loss in left ventricle during diastolic and systolic phases in elderly patients.

BACKGROUND: The change of left ventricular function deteriorated with age because of gradual increases of blood pressure may result in increased energy loss (EL) in left ventricle (LV). The present study investigated EL in LV among hypertensive elderly patients and examined factors contributing to EL. METHODS: A single-center retrospective study was performed on elderly hypertensive outpatients (≥65 years) who underwent echocardiography (N = 105). EL in the LV was measured using a vector flow mapping system, and factors affecting peak EL during the early-diastolic phase (ED-EL), late-diastolic phase (LD-EL), and systolic phase (Sys-EL) were evaluated. RESULT: Mean age was 79.9 ± 6.4 years (male 43%). Mean ED-EL, LD-EL, and Sys-EL were 42.1 ± 46.7, 75.6 ± 60.2, and 40.4 ± 40.2 mJ/N/s. In a stepwise regression analysis, the E/e'(lateral) (unstandardized B = 0.005, 95%CI -0.03 to 0.007, standardized ß = 0.434, P < .001) was identified as factors affecting ED-EL. The factors affecting LD-EL were E/A ratio (B = -0.122, 95%CI -0.176 to -0.068, ß = -0.470, P < .001) and time velocity integral (TVI) in LVOT (unstandardized B = 0.002, 95%CI 0.000 to 0.004, ß = 0.247, P = .021). The factors influencing Sys-EL were TVI in LVOT (B = 0.002, 95%CI 0.001 to 0.004, ß = 0.390, P < .001), E/A ratio (B = -0.054, 95%CI -0.093 to -0.015, ß = -0.258, P = .008), left ventricular outflow tract (LVOT) diameter (B = -0.006, 95%CI -0.010 to -0.002, ß = -0.307, P = .006), and left ventricular mass index (B = 0.000, 95%CI 0.000 to 0.001, ß = 0.208, P = .039). CONCLUSION: Peak EL in the LV was higher during diastolic phase than systolic phase among elderly hypertensive patients. Peak EL both during late-diastolic phase and systolic phase was affected by systolic blood flow in LVOT and LV transmitral flow pattern.

Minor ST-T changes on electrocardiograms are associated with reduced constructive myocardial work in hypertensive patients with a preserved ejection fraction.

Minor ST-T changes on electrocardiograms are observed in patients with hypertensive heart disease with a preserved left ventricular ejection fraction (LVEF); however, the relationship between minor ST-T changes and global myocardial work on echocardiograms remains unclear. We evaluated the global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) in 186 hypertensive patients with preserved LVEF (>50%) using an offline analysis system (View Pal, GE). Minor ST-T changes as well as major ST-T changes (depression in ST in lead V5 > 1 mV) were also evaluated by electrocardiography. The mean age was 79.4 ± 8.2 years (men 37.6%). Patients with minor and major ST-changes had a smaller absolute GLS (-20.3 ± 3.1, -18.2 ± 3.7, and -15.2 ± 5.0%, P < 0.001) and a smaller constructive workload [GWI (2148 ± 486, 1938 ± 462, and 1685 ± 701 mmHg%, P = 0.002) and GCW (2419 ± 510, 2185 ± 466, and 1865 ± 702 mmHg%, P < 0.001)] than those with no ST-T changes. Additionally, patients with minor and major ST-T changes had increased wasted myocardial work [GWW (87 ± 61, 105 ± 56, and 127 ± 75 mmHg%, P = 0.045)], which resulted in reductions in the myocardial work efficiency [GWE (95 ± 4, 94 ± 3, and 89 ± 12%, P < 0.001)]. Even after adjustments for confounding factors, including EF, diastolic function parameters, LV hypertrophy, history of heart failure and atrial fibrillation, patients with minor ST-T changes had significantly smaller LV global constructive work in comparison to those without [GWI (2260 ± 33 vs. 2025 ± 76 mmHg%, P = 0.007) and GCW (2501 ± 45 vs. 2210 ± 105 mmHg%, P = 0.003)]. In conclusion, in hypertensive patients with preserved LVEF, minor ST-T changes on electrocardiograms were associated with reduced constructive work in the LV.