Isradipine for the treatment of hypertension following coronary artery bypass graft surgery: a randomized trial versus sodium nitroprusside.

In a randomized trial, a calcium antagonist, isradipine (ISR) and sodium nitroprusside (SNP) were compared in the management of hypertension in the early period following coronary artery bypass grafting (CABG). Patients with a mean arterial pressure (MAP) of greater than 100 mmHg were treated with a 6 h i.v. infusion of ISR (n = 98) or SNP (n = 100). Mean MAP at baseline was 113 (ISR) and 112 mmHg (SNP). Blood pressure control (MAP less than or equal to 90 mmHg within 25 min) was achieved in 92% (ISR) and 84% (SNP), within a mean of 12 and 15 min, respectively (P less than 0.01 between groups). At 25 min, mean percentage changes from baseline for ISR and SNP were: MAP -24.3% vs. -21.4% (P less than 0.05), heart rate +4.1% vs. +8.4% (P less than 0.01), rate-pressure-product -16.9% vs. -10.6% (P less than 0.001), cardiac index +19.2% vs. +4.6% (P less than 0.001), stroke volume index +16.1% vs. -1.9% (P less than 0.001), and peripheral vascular resistance -35.4% vs. -22.0%, (P less than 0.001). Treatment was discontinued before 6 h in 24 patients in each group because of low blood pressure. Hypotension (MAP less than 70 mmHg) and tachycardia were less frequent with ISR than with SNP. In conclusion, ISR is effective and well tolerated in the treatment of hypertension following CABG, and has a haemodynamic profile which may be more favourable than that seen after treatment with SNP.