Randomized and double-blind controlled clinical trial of extracorporeal cardiac shock wave therapy for coronary heart disease.

Our aim was to evaluate the safety and effectiveness of extracorporeal cardiac shock wave therapy (CSWT) for the patients with coronary heart disease (CHD) using a randomized, double-blind, controlled clinical trial design. Twenty-five patients with CHD were enrolled in this study. Fourteen of the patients were randomized into the CSWT group and 11 into the control group. We applied the CSWT procedure to each patient by using nine shock treatments during 3 months, but the shock wave (SW) energy was only applied to the patients in the CSWT group and not to the patients in the control group. Technetium-99m sestamibi myocardial perfusion, fluorine-18 fluorodeoxyglucose myocardial metabolism single-photon emission computed tomography (SPECT), and two-dimensional echocardiography were performed to identify segments of myocardial ischemia, myocardial viability, and ejection fraction before and after CSWT. We also followed the patients to evaluate adverse effects. After CSWT, the New York Heart Association class, the Canadian Cardiovascular Society angina scale, nitroglycerin dosage, myocardial perfusion and myocardial metabolic imaging scores of dual-isotope SPECT in the CSWT group were reduced significantly (P = 0.019, 0.027, 0.039, 0.000, 0.001, respectively), and the Seattle Angina Questionnaire scale, 6-min walking test, and left ventricular ejection fraction were increased significantly (P = 0.021, 0.024, 0.016, respectively) compared with those before the SW treatment. All of the parameters in the control group did not change significantly after the treatment (all P > 0.05). No serious adverse effects of CSWT were observed. Cardiac shock wave therapy is a safe and effective treatment for CHD patients.

[Effects of extracorporeal cardiac shock wave therapy in patients with ischemic heart failure].

OBJECTIVE: To evaluate the feasibility, safety and efficiency of extracorporeal cardiac shock wave therapy (CSWT) in patients with ischemic heart failure. METHODS: Fifty patients with ischemic heart failure and left ventricular ejection fraction (LVEF) < 50% were randomized to CSWT (shots/spot at 0.09 mJ/mm(2) for 9 spots, 9 times within 3 month) or control group. Dual isotope simultaneous acquisition single-photon emission computed tomography with (99)Tc(m)-sestamibi/(18)F-fluorodeoxyglucose ((99)Tc(m)-MIBI/(18)F-FDG) was performed before randomization and at 1 month after CSWT/control to locate and evaluate viable myocardium region. Canadian cardiovascular society (CCS) class sores, NYHA, Seattle Angina Questionnaire (SAQ), 6-min walk test (6 MWT), left ventricular ejection fraction (LVEF), left ventricular end-diastolic dimension (LVEDD) and the dosage of nitroglycerin use were compared between two groups at each time point. RESULTS: All patients completed the study protocol without procedural complications. At 1 month, patients in CSWT group experienced improvement in NYHA (P < 0.01), CCS (P < 0.01), SAQ (P = 0.021), 6 MWT (P = 0.012) and dosage of nitroglycerin use (P < 0.01) compared to baseline. LVEF [45.0 (39.0, 48.0) vs. 47.0 (42.0, 50.0) P = 0.001], LVEDD [58.0 (56.0, 59.0) vs. 56.0 (55.0, 58.0) P = 0.002], summed perfused score [23.0 (20.5, 24.5) vs. 20.0 (18.0, 22.0) P < 0.01] and metabolic score [25.0 (23.0, 26.0) vs. 24.0 (21.5, 25.0) P = 0.028] were also improved in CSWT group. All these parameters remained unchanged in control group between baseline and at 1 month. CSWT was independent factor for improved cardiac function, quality of life and echocardiography parameters after adjusting for known factors which might affect outcome. CONCLUSION: CSWT could improve symptom, cardiac function, quality of life and exercise tolerance in patients with ischemic heart failure, CSWT might serve as a new, non-invasive, safe and efficient therapy for these patients.

Cardiac resynchronization therapy (CRT) with right ventricular sense triggered left ventricular pacing benefits for the hemodynamics compared with standard CRT for chronic congestive heart failure: A cross-over study.

BACKGROUND: The aim of this study was to investigate the effect of cardiac resynchronization therapy (CRT) with right ventricular (RV) sense triggered left ventricular (LV) pacing for chronic heart failure (CHF). METHODS: Thirty patients who were eligible for the Class I indication of CRT were enrolled and the informed consents were signed. Left ventricular ejection fraction (LVEF), diastolic mitral flow velocity time integral (VTI), mitral regurgitation flow VTI, and aortic valve flow VTI were measured with GE Vivid 7 (GE Medical, Milwaukee, WI, USA) before and after CRT. The echocardiographic measurements and the average annual costs of the device use were compared. RESULTS: The duration of QRS complex, the length of time used for optimization, and the average annual cost of the device use under RV sense triggered LV pacing were significantly less than that under standard biventricular (BiV) pacing (p < 0.01), while the average battery lifetime was longer. Subgroup analysis showed that LVEF, diastolic mitral flow VTI, and aortic valve flow VTI under RV sense triggered LV pacing were greater than that under standard BiV pacing with right or LV pre-activation. The average battery lifetime was significantly longer and the average annual cost of the device use was less. The mitral regurgitation flow VTI under RV sense triggered LV pacing was less than that under standard BiV pacing with RV pre-activation. CONCLUSIONS: RV sense triggered LV provides benefits for CHF patients over standard CRT in terms of maintaining the physiological atrio-ventricular delay of atrio-ventricular node and improving the acute hemodynamic effects.

A prospective study to evaluate the efficacy of an intracardiac electrogram-based atrioventricular and interventricular intervals optimization method in cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) with biventricular pacing improves cardiac function, functional capacity and quality of life in selected patients with heart failure. The current study aimed to evaluate the efficacy of the intracardiac electrogram (IEGM)-based optimization method, QuickOpt(TM), in Chinese patients treated with CRT. METHODS: Aortic time velocity integrals (AVTI) achieved at the sensed atrioventricular (AV), paced AV and interventricular (VV) interval settings recommended by both QuickOpt(TM) and standard echocardiographic optimization were measured in 101 patients. Consistency and the strength of the relationship between the two timing cycle optimization methods were assessed by intra-class correlation coefficient (ICC). RESULTS: The ICC showed good agreement and correlation with what the AVTI achieved at the optimal sensed AV (ICC = 0.9683 (0.9535 - 0.9785)), paced AV (ICC = 0.9642 (0.9475 - 0.9757)) and VV (ICC = 0.9730 (0.9602 - 0.9817)) interval settings determined by the two optimization methods. The average time required by echocardiographic optimization and by QuickOpt(TM) were (78.32 ± 32.40) minutes and (1.98 ± 1.64) minutes respectively (P < 0.0001). CONCLUSION: The QuickOpt(TM) algorithm provides a quicker, simpler and reliable alternative to the standard method for timing cycle optimization.

Initial experiences of maintaining atrioventricular intrinsic conduction during cardiac resynchronization therapy in non-responders.

BACKGROUND: Cardiac resynchronization therapy (CRT) is a major breakthrough in therapy for advanced heart failure patients; however, a number of key clinical research questions remain, perhaps most importantly the issue of why apparently suitable patients do not respond to CRT. METHODS: Seven patients, six males and one female, aged (56.43 +/- 6.13) years, all diagnosed with dilated cardiomyopathy, were included in this study. They were all non-responders to CRT who underwent routine optimization postoperatively, and received optimal drug therapy. On the basis of biventricular pacing, titrating various atrioventricular (AV) intervals were performed to get the true fusional QRS complexes composed of biventricular pacing and AV intrinsic conduction. Then, the effects of AV intrinsic conduction during CRT were evaluated. RESULTS: On the setting of AV intrinsic conduction during CRT, the true fusional QRS complexes were the narrowest, and all patients showed alleviation of symptoms, improvement of exercise tolerance, life quality and hemodynamic parameters during more than 6 months of follow-up. CONCLUSIONS: Titrating AV intervals to get the true fusional QRS complexes composed of biventricular pacing and AV intrinsic conduction will be beneficial for non-responders to CRT. Maintaining AV intrinsic conduction during CRT may decrease the rates of non-responders to CRT.