Cardiac shockwave therapy in patients with chronic refractory angina pectoris.

BACKGROUND Cardiac shockwave therapy (CSWT) might improve symptoms and decrease ischaemia burden by stimulating collateral growth in chronic ischaemic myocardium. This prospective study was performed to evaluate the feasibility and safety of CSWT. METHODS We included 33 patients (mean age 70 ± 7 years, mean left ventricular ejection fraction 55 ± 12 %) with end-stage coronary artery disease, chronic angina pectoris and reversible ischaemia on myocardial scintigraphy. CSWT was applied to the ischaemic zones (3-7 spots/session, 100 impulses/spot, 0.09 mJ/mm(2)) in an echocardiography-guided and ECG-triggered fashion. The protocol included a total of 9 treatment sessions (3 treatment sessions within 1 week at baseline, and after 1 and 2 months). Clinical assessment was performed using exercise testing, angina score (CCS class), nitrate use, myocardial scintigraphy, and cardiac magnetic resonance (CMR) 1 and 4 months after the last treatment session. RESULTS One and 4 months after CSWT, sublingual nitrate use decreased from 10/week to 2/week (p < 0.01) and the angina symptoms diminished from CCS class III to CCS class II (p < 0.01). This clinical improvement was accompanied by an improved myocardial uptake on stress myocardial scintigraphy (54.2 ± 7.7 % to 56.4 ± 9.4 %, p = 0.016) and by increased exercise tolerance at 4-month follow-up (from 7.4 ± 2.8 to 8.8 ± 3.6 min p = 0.015). No clinically relevant side effects were observed. CONCLUSION CSWT improved symptoms and reduced ischaemia burden in patients with end-stage coronary artery disease without relevant side effects. The study provides a solid basis for a randomised multicentre trial to establish CSWT as a new treatment option in end-stage coronary artery disease.