Clinical impact of medical intensive treatment on functional class in patients initially diagnosed as refractory angina

Abstract

Introduction: Refractory angina is a major clinical challenge. Patients (pt) usually have significant functional impairment due to disabling symptoms, which greatly adversely impact their quality of life. Many pt may be erroneously diagnosed as refractory angina, if not on intensive medical therapy. Objectives: To evaluate the impact of intensive medical treatment on angina functional class in pt initially diagnosed as refractory angina. Methods: 45 pt (31 men, 59±13 years) were included based on the following criteria: 1) disabling symptoms; 2) objectively documented myocardial ischemia; 3) coronary anatomy unsuitable for myocardial revascularization procedures. Medical visits were scheduled every 4 weeks during a 3-month period (Vo to V3). Angina functional class was recorded in each visit as proposed by the Canadian Cardiovascular Society (CCS). Medical therapy was strongly encouraged to be optimized based on patient’s tolerance. Statistical analysis included the Student s t-test (continuous variables), the chi-square test (categorical variables), and the Wilcoxon test (changes in functional class). Results: There was an overall improvement in CCS class between V0 to V3 (p,<0,001), with 30 pt (66.7%) improving at least 1 class. In 14 pt (31.1%) there was no difference and in only 1 pt (2.2%) there was worsening of CCS class. In V0 and V3, anti-ischemic drugs were used as follows (%), respectively: beta-blockers (96 vs. 96), calcium channel blockers (78 vs. 84), long-acting nitrates (96 vs. 100), and trimetazidine (38 vs. 93). Mean daily dosages (mg)of selected drugs were: atenolol 105±49 to 113±59 (P=0.16); carvedilol 44±16 to 55±20 (P=0.06); amlodipine 7±3 to 8±3(P=0.12); isossorbide 95±28 to 106±24(P=0.09). There was a non-significant 4.4% decrease in the mean heart rate (bpm) from 66±11 to 63±9(P=0.10), and a non-significant 4% reduction in mean systolic (SBP) and diastolic (DBP) blood pressure: SBP - 128±23 to 123±23mmHg (P=0.10), and DBP -75±11 to 72±14mmHg (P=0.11). Conclusion: Pt enrolled in this clinical program, although initially diagnosed as refractory angina, experienced a significant improvement in their functional class. This could not be attributed to an increase in anti-ischemic drugs or to an hemodynamic effect. We believe that the regular visits at shorter intervals may have led to a better treatment adherence, emotional easiness and self-confidence. This study exemplifies how complex is the relationship between extensiveness of the disease and functional impairment.