Evaluation of guideline-based cardiovascular medications and their respective doses in heart failure patients in Oman

Background Significant gaps exist between guidelines and practice in the management of heart failure, not only in Oman but the Arabian Gulf region in general. Currently, only limited research exists on the use of these guideline-based cardiovascular medications and their corresponding target doses in the region. Objective To evaluate the use of guideline-based cardiovascular medications and their corresponding target doses in heart failure patients with reduced (< 40%) and mid-range (40-49%) ejection fraction in Oman. Setting Cardiology clinics at Sultan Qaboos University Hospital, Muscat, Oman. Methods The study included heart failure patients seen at the clinics between January 2016 and December 2019. The use of angiotensin-converting-enzyme inhibitors (captopril, lisinopril) or angiotensin II receptor blockers (irbesartan, valsartan), β-blockers (bisoprolol, carvedilol) and spironolactone along with their respective target doses were evaluated as per the European, American, and Canadian heart failure guidelines. Analyses were performed using univariate statistics. Main outcome measure The proportion of patients that was prescribed guideline-based heart failure medications along with their target doses as per guidelines. Results The overall mean age of the cohort (N = 249) was 63 ± 15 years and 61% (n = 151) were males. Seventy-one percent (n = 177) of the patients had heart failure with reduced ejection fraction while 29% (n = 72) had heart failure with mid-range ejection fraction. A total of 87% (n = 216), 62% (n = 154) and 39% (n = 96) of the patients were on β-blockers, angiotensin-converting-enzyme inhibitors/angiotensin II receptor blockers and spironolactone, respectively. Only 33% (n = 81) of the patients were on the triple guideline-based cardiovascular medication classes concurrently. Patients with reduced ejection fraction were more likely to be prescribed the triple guideline-based cardiovascular medication classes concurrently than those that had heart failure with mid-range ejection fraction (37% vs 22%; p = 0.027). A total of 100% (96/96), 56% (121/216) and 42% (64/153) of the patients were prescribed ≥ 50% of target dose for spironolactone, β-blockers and angiotensin-converting-enzyme inhibitors/angiotensin II receptor blockers, respectively. Conclusions The use of guideline-based cardiovascular medications in heart failure patients with reduced and mid-range ejection fraction is low in Oman. They were also largely not optimally dosed at target levels.