Coronary Sinus Reducer implantation improves symptoms, ischaemia and physical capacity in patients with refractory angina unsuitable for myocardial revascularisation: A single-centre experience

Aims: The aim of this study was to evaluate the clinical efficacy of Coronary Sinus Reducer implantation in alleviating angina symptoms and improving objective ischaemia parameters and indices of physical capacity. Methods and results: Patients with refractory angina (Canadian Cardiovascular Society [CCS] class 3-4) were treated with the Reducer. Baseline and follow-up evaluation consisted of clinical assessment including completion of the Seattle Angina Questionnaire (SAQ) and CCS class evaluation, and objective assessment by treadmill exercise test, dobutamine echocardiography and six-minute walk test (6MWT). Overall, 48 patients (40 male) were enrolled. No periprocedural or long-term adverse events were recorded. CCS class diminished from a mean of 3.4±0.5 at baseline to 2.0±1 (p<0.001), and all domains of the SAQ improved significantly following Reducer implantation. Mean exercise duration increased from 03:43±01:30 to 04:36±02:18 min:sec (p=0.025) and 6MWT distance increased from 299.9±97.9 m to 352.9±75.3 m (p=0.002). Ejection fraction (EF%) at stress increased from 51.0±10 to 56.5±10 (p=0.004), and wall motion score index improved from 1.58±0.4 to 1.37±0.3 (p=0.004). Conclusions: Reducer implantation for the treatment of refractory angina is a simple and safe procedure which significantly alleviates symptoms of angina and improves objective ischaemia parameters and indices of physical function.