Changes in left ventricular function in untreated hypertensive female - an assessment at rest and during exercise with radionuclide ventriculography

Aim: The aim of this study was to investigate left ventricular function at rest and during exercise in untreated newly diagnosed female hypertensive patients. Patients and methods: Seventeen female patients with newly established, uncomplicated essential hypertension (aged 25 to 57 years) were examined, and were compared to 23 female normotensive volunteers of comparable age. Investigations were performed at rest and during maximum physical exercise by means of radionuclide equilibrium ventriculography on Siemens ZLC gamma camera, attached to ADAC 3300 computer system. Studies were acquired in the “ best septal” left anterior oblique projection on a 64 x 64 matrix, with 32 frames/cardiac cycle, zoom 1.5, after in vivo labeling of red blood cells by 740-1110 MBq Tc-99m. The following paremeters of left ventricle were analized: ejection fraction (EF), end- diastolic (EDV) and end-systolic volume (ESV), cardiac output (CO), peak ejection rate (PER) and time to PER, peak filling rate (PFR) and time to PFR. Results: Mean blood pressure were significantly higher in patients at rest and during exercise than in controls (121± ; 13 vs. 89± ; 7 mm Hg, and 143± ; 11 vs. 122± ; 9 mm Hg, respectively, p<0.001). At peak exercise patients and controls achieved a similar workload and exercise duration. Increase in heart rate during exercise was similar in patients and controls (from 72 ± ; 8 to 142 ± ; 16 vs. 75 ± ; 10 to 138 ± ; 14 beats/min, respectively). At rest, there were no significant difference in EDV, ESV and CO of left ventricle between two groups. During stress, EDV and CO were significantly higher in patients (91 ± ; 13 vs. 68 ± ; 11 ml/m2 ; and 6.8 ± ; 2.2 vs. 4.7 ± ; 1.6 l/min/m2, respectively, p<0.01), while ESV was similar in both groups. There was no significantly difference in EF at rest and stress between patients and controls (54 ± ; 10 vs. 55 ± ; 8%, and 70 ± ; 10 vs. 66 ± ; 8%, respectively, NS), but % rise in EF during exercise was significantly higher in patients (19.8 ± ; 8 vs. 13.7 ± ; 7%, p<0.05). PER i TPER at rest and exercise were similar in both group. No difference was observed at rest in PFR (2.88 ± ; 0.79 vs. 2.76 ± ; 0.76 EDV/s, NS) and TPFR (143 ± ; 62 vs. 146 ± ; 42 ms, NS), not either in stress (PFR 5.85 ± ; 1.86 vs. 6.21 ± ; 1.97 EDV/s, NS ; TPFR 97 ± ; 20 vs. 91 ± ; 19 ms, NS). Conclusion: Female patients with newly diagnosed, untreated hypertension have preserved maximal exercise performance, and systolic and diastolic function of left ventricle, but they have significant enlargement of left ventricular EDV and elevated left ventricular CO during exercise.