Assessment of Left Ventricular Function and Contractile Reserve in Patients with Hypertension

Background: Hypertension is a prevalent and well-recognized cardiovascular risk factor, which may lead to left ventricular (LV) systolic impairment through chronic pressure overload. Aim of the work: An impaired contractile reserve (CR) may be an early manifestation of left ventricular (LV) systolic dysfunction in hypertensive patients. Using normotensive patients as controls, we examined LV CR and its correlates in hypertensive patients. Material and methods: The study was conducted prospectively on fifty cases. 30 cases (24 males and 6 females aged 55.57 ± 10.07) had hypertension. All patients were subjected to complete history taking including comorbidities, risk factors and full clinical examination. Patients with significant coronary or valvular disease, previous myocardial infarction or revascularization and diabetes were excluded. LV ejection fraction (LVEF) & global longitudinal strain (GLS) were measured at rest and at low-dose dobutamine. Results: Hypertensive patients, compared to control had significantly impaired GLS at rest (-19.00 ± 2.34% vs. -20.50 ± 1.52%, P <0.015) and at low dobutamine dose (-19.90 ± 2.33% vs. -22.60 ± 1.88 %, P <0.001). Absolute and relative GLS CR were significantly lower in hypertensive patients (-0.88 ± 0.45% vs.-2.12 ± 0.77% and 4.70 ± 2.76% vs. 10.33 ± 3.78 %, respectively, both P < 0.001). Absolute and relative LVEF CR were significantly lower in hypertensive patients (3.31 ± 0.97 % vs. 7.09 ± 1.67% and 5.37 ± 1.64% vs. 11.61 ± 3.19%, respectively, both P < 0.001). Conclusion: Compared to control, hypertensive patients with no other co-morbidities had impaired LV GLS at rest and impaired CR despite normal LVEF.