Extracorporeal Cardiac Shock Wave Therapy(CSWT) in Patients with Severe Coronary Artery Disease(CAD) Unsuitable for Percutaneous Coronary Intervention (PCI) and Coronary Artery Bypass Graft Surgery (CABG) Guided by Echocardiography

Abstract

To test the effectiveness and feasibility of extracorporeal CSWT in patients (pts) with severe CAD unsuitable for PCI and CABG. 51 pts were enrolled. They were 35 men and 16 women aged from 41 to 89 years old (67.5 +10.9). Extracorporeal CSWT was performed with the application of 100 shocks/spot at 0.09 millijoules/mm2 (mJ/mm2) energy flux density for 3-9 spots each time with three times per week at each series for three series at 1, 5, 9 weeks. The location and depth of CSWT application were based on thallium 201 myocardial perfusion scan findings guided by echocardiography. The exercise tolerance, thallium 201 myocardial perfusion scan and echocardiography were followed up 6 months later. These 51 patients received 1500 to 7500 low intensity shock waves during entire treatment course with an average of 4682 + 1293 shock waves. Exercise duration with Bruce protocol increased from 304 + 148 seconds before CSWT to 350 + 115 seconds after 6 months (p< 0.0174). The CCS angina score was decreased from 2.9 before CSWT to 2.0 after 6 months (P< 0.001). 39(76%) pts had perfusion improvement by thallium 201 myocardial perfusion scan. Echocardiographic study showed left ventricular (LV) end-diastolic dimension and volume were decreased significantly from 55.0 + 8.5 mm and 152.2 + 57.2 mm3 to 53.1 + 8.1 mm and 140.5 +52.8 mm3 after 6 months (P=0.0185, P= 0.0232). LV systolic dimension decreased from 36.8 + 8.8 mm before CSWT to 34.6 + 9.2 mm after 6 months (P =0.006). LV systolic volume changed from 62.5 + 37.8 mm3 to 55.0 + 38.5 mm3 (P= 0.0282). LV ejection fraction increased from 60.0 + 12.6% before CSWT to 63.5 + 12.7% after 6 months. (P =0.032). Regional wall motion score index was decreased from 1.30 + 0.36 before CSWT to 1.21 + 0.30 after 6 months (P= 0.0024). No side effects related to CSWT were found. Our study demonstrated that echocardiography can be used as a guide for performing extracorporeal CSW. And CSWT can improve angina symptoms, increase exercise duration and improve myocardial perfusion, left ventricular remodeling, myocardial wall motion and finally improve left ventricular ejection fraction. Our study also demonstrated that CWST is safe and effective. This kind of therapy can be applied to the pts of severe CAD with refractory angina unsuitable for PCI or CABG.