经食管心房调搏对阵发性室上性心动过速的诊断价值

目的 探讨经食管心房调搏对阵发性室上性心动过速的分型及定位诊断价值。方法 回顾性分析食管心房调搏对193例阵发性室上性心动过速分型及定位诊断结果，并与心内电生理检查诊断结果比较。结果 经食管心房调搏对慢-快型AVNRT及顺向性AVRT的诊断敏感性、特异性、准确性均较高，对少见型AVNRT的诊断敏感性低(25％)。结论 阵发性室上性心动过速发作时食管与体表心电图P^-波起始与极性是诊断阵发性室上性心动过速的关键。经食管心房调搏对心动过速旁道定位误诊原因主要是心动过速时体表心电图P^-波往往与T波融合，导致V1、I导联P^-波极性及V1导联P^-波起始部形态改变。     

Assessment of abnormal left atrial relaxation by transesophageal pulsed doppler echocardiography of pulmonary venous flow velocity

Background: Several studies on left ventricular relaxation have been undertaken in the past: however, left atrial (LA) relaxation has not been fully evaluated. Hypothesis: The purpose of this study was to assess abnormalities in LA relaxation by evaluating pulmonary venous flow velocity and interatrial septal motion using transesophageal echocardiography. Methods: The subjects were 56 untreated patients in sinus rhythm, including 25 with previous myocardial infarction, 9 with hypertrophic cardiomyopathy, 11 with dilated cardiomyopathy, as well as 11 with chest pain syndrome as controls. Peak first systolic velocity (PVS₁), peak atrial systolic velocity (PVA), and their time-velocity integrals (PVS₁-I and PVA-I, respectively) were calculated from the pulmonary venous flow velocity. Results: The PVS₁ and PVS₁-I correlated negatively with the maximum LA dimension and mean pulmonary capillary wedge pressure, and correlated positively with the amplitude of the interatrial septal motion during LA relaxation and percent fractional LA relaxation. The PVA and PVA-I did not correlate with the mean pulmonary capillary wedge pressure. There was a weak positive correlation between PVA and PVS₁, and a close positive correlation between the ratio of PVA to PVS₁ and mean pulmonary capillary wedge pressure. Multiple regression analysis indicated that the PVS₁ was most closely related to percent fractional LA relaxation, followed by mean pulmonary capillary wedge pressure. Conclusion: The PVS₁ determined from the pulmonary venous flow velocity is closely related to parameters of LA relaxation which may be determined by transesophageal M-mode echocardiography, and the ratio of PVA to PVS₁ is useful for noninvasive evaluation of LA pressure..     

Prognostic value of left ventricular volume response during dobutamine stress echocardiography

AIMS: An abnormal left ventricular volume response during dobutamineechocardiography identified patients with severe coronary arterydisease. The aim of the study was to assess the prognostic valueof left ventricular volume changes during dobutamine stressechocardiography in 136 patients. MEHTODS AND RESULTS: Endpoints were defined as spontaneous cardiac events at follow-up.Left ventricular end-diastolic and end-systolic volume changes(abnormal response: >10% and >20> decrease, respectively)were compared with other clinical and stress test variables.During 18±7 months of follow-up, 31 cardiac events occurred:12 hard events (cardiac death [n=6 myocardial infarction [n=6])and 19 soft events (unstable angina [n=16] congestive heartfailure [n=3] End-diastolic volume response (P=0·006),diabetes (P=0·008), inducible wall motion abnormalities(P=0·024), end-systolic volume response (P=0·039)and inducible angina (P=0·038) were related to a greaterlikelihood of cardiac events. The Cox regression analysis revealedend-diastolic volume response (odds ratio: 3·0; CI 1·44–6·32)and diabetes (odds ratio: 2·7; CI 1·28–5·69)to be independent predictors of spontaneous cardiac events.Diabetes (odds ratio: 4·0; CI 1·26–12·80)and >40% baseline ejection fraction (odds ratio: 2·21;CI 1·14–4·29) were independent predictorsof hard events. CONCLUSIONS: An abnormal end-diastolic volume response during dobutaminestress echocardiography identifies patients with an unfavourableoutcome; they should be considered for more accurate prognosticstratification.     

Catheter ablation and antiarrhythmic drugs for haemodynamically tolerated post-infarction ventricular tachycardia; long-term outcome in relation to acute electrophysiological findings.

AIMS: Radiofrequency catheter ablation is effective at terminating ventricular tachycardia, but the overall clinical role of the technique in patients with a prior myocardial infarction is still debated, due to the uncertainties of the long-term reliability of the procedure. The purpose of this study was to prospectively investigate the relationship between acute results obtained by catheter ablation and long-term outcome in a homogeneous population of patients with post-myocardial infarction ventricular tachycardia. METHODS AND RESULTS: One hundred and twenty-four consecutive patients with recurrent, drug-refractory, haemodynamically tolerated ventricular tachycardia were included in the study. This population accounted for 30% of the patients with post-myocardial infarction ventricular tachycardia admitted between April 1992 and September 1997 to the investigating centres. The ablation was successful in eliminating sustained ventricular tachycardia in 91 of them (73%); a partial result was obtained in 21 (17%) and failure in 12 (10%). Low dose amiodarone and/or beta-blockers were maintained in 86% of the patients. Over a median follow-up of 41.5 months (interquartile range 30.5-59.5 months), there were 15 deaths (12%), three of which were sudden (2.4%); the 12 remaining patients died of heart failure. Event-free survival analysis showed a significantly lower ventricular tachycardia recurrence rate in patients with a successful procedure as compared to those with failure or a partial result (19% vs 53% at one year and 27% vs 60% at 3 years, P=0.003). A repeat procedure was performed in 15 patients with early recurrences and was followed in all by long-term success. Of those who submitted to a second procedure, 93/124 patients (75%) are free of ventricular tachycardia recurrences. An implantable cardioverter-defibrillator (ICD), following procedure failure, was implanted in 13 patients (11%) of the study population. CONCLUSIONS: Radiofrequency catheter ablation is effective in a wide population of patients with recurrent tolerated ventricular tachycardia, with very low sudden death and cardiac mortality rates over the long-term. Persistent ventricular tachycardia inducibility after catheter ablation requires an ICD implant and/or repeat ablation.     

Classification of Heart Failure According to Ejection Fraction: JACC Review Topic of the Week

The recent U.S. Food and Drug Administration expanded indication for sacubitril/valsartan introduces a new potential taxonomy for heart failure, with no reference to “preserved” ejection fraction but referring to “below normal” ejection fraction as those most likely to benefit. This review summarizes the evolution of nomenclature in heart failure and examines evidence showing that patients with ejection fraction in the “mid range” may benefit from neurohormonal blockade similar to those with more severely reduced (<40%) ejection fraction. Furthermore, prominent sex differences have been observed wherein the benefit of neurohormonal blockade appears to extend to a higher ejection fraction range in women compared to men. Based on emerging evidence, revised nomenclature is proposed defining heart failure with “reduced” (<40%), “mildly reduced,” and “normal” (≥55% in men, ≥60% in women) ejection fraction. Such nomenclature signals consideration of potentially beneficial therapies in the largest group of patients with reduced or mildly reduced ejection fraction.     

经心内和食管快速心房刺激对P波时限及离散度的影响

目的分析快速心房刺激对P波时限及离散度的影响。方法在74例射频消融术经电极导管起搏高位右房及82例经食管心房调搏检查者中,用180次/分的S1S1刺激心房3min,在刺激前后立刻记录12导同步心电图,通过心电图测出刺激前后的最大P波时限(Pmax)、最小P波时限(Pmin)及P波离散度(Pd),然后进行比较。结果:射频消融组Pmax在心房刺激后比刺激前有显著性延长(P<0.01),Pmin及Pd无显著性差异。食管心房调搏组Pmax及Pd在心房刺激后显著性增加(P<0.01),Pmin无显著性差异。结论:快速心房刺激能引起心房传导时间延长,非均质电活动的离散程度增加。     

Cardiac resynchronization devices: the Food and Drug Administration's regulatory considerations

Cardiac resynchronization therapy (CRT) devices have been studied clinically since 1998, and have been on the U.S. market since the Food and Drug Administration (FDA) approval of the first product in 2001. Since that time, the FDA has approved many different models from three different manufacturers, representing the first and second generations of these products. All of these products have undergone the FDA pre-market approval process, which examines the safety and effectiveness of the devices for their intended use. Over the last several years, the FDA has adapted recommendations for CRT clinical trials based on an evolving understanding of what these devices can achieve. This paper will outline the dynamic nature of the FDA's approval process for CRT devices and briefly review the clinical trial designs for the first generation devices.     

Cardiovascular Effects of a Single Slow Release Lanreotide Injection in Patients with Acromegaly and Left Ventricular Hypertrophy

In our study we assessed the effects of a single i.m. injection of slow-release Lanreotide (30 mg) (SR-L), a new long-acting somatostain analog, on circulating GH levels, baseline cardiac function (M-mode, 2D guided, doppler-echocardiographic study) and cardiopulmonary response to exercise (cycloergometric test, performed using a computer drived, electrically braked cycle ergometer), tested at baseline, after 7 and 14 days from the injection in 10 acromegalic patients (5 M, 5 F, mean age 57.7 ± 3.1 yrs, body mass index (BMI) 27 ± 0.8 kg/m², blood pressure 141 ± 6.5/82 ± 3 mmHg). SR-L administration decreased GH levels in acromegalic patients (mean±SEM) from 16.1 ± 6.9 to 10.8 ± 5.1 µg/L (p = 0.045) after 7 days and to 11.9 ± 5 µg/L (p = 0.078) after 14 days from the injection. Moreover, we observed a significant (p<0.05) decrease in systolic blood pressure and heart rate at the 7th (135 ± 6.1 vs 141 ± 6.5 mmHg, and 68 ± 2.1 vs 74 ± 2.1 bpm) and 14th (137 ± 6.2 vs 141 ± 6.5 mmHg, and 72 ± 2 vs 74 ± 2.1 bpm) day of the study with respect to the baseline values. After SR-L administration we also found an increase in ejection fraction (69 ± 2 vs 63 ± 2.3% at 7th day, p = 0.006; 65 ± 2.3 vs 63 ± 2.3% at the 14th day, p = 0.027) and shortening fraction (40.8 ± 1.8 vs 36.6 ± 1.9% at 7th day, p = 0.005; 38.7 ± 1.8 vs 36.6 ± 1.9% at the 14th day, p = 0.045). The positive acute cardiac response to SR-L injection was also demonstrated by the increase in A/E velocity ratios at 7th (1.14 ± 0.1 vs 0.98 ± 0.07, p = 0.016) and 14th (1.04 ± 0.08 vs 0.98 ± 0.07, p = 0.008) day of the study. After SR-L injection, exercise capacity and VO₂ at anaerobic thresold were also increased with respect to the baseline test: 61.1 ± 8.2 vs 38.9 ± 6.8 watts (p = 0.002) and 1012.4 ± 71.5 vs 915.3 ± 77.8 mL/min (p = 0.033) after 7 days, and 61.4 ± 7.2 vs 38.9 ± 6.8 watts (p = 0.002) and 1010.1 ± 62.5 vs 915.3 ± 77.8 mL/min (p = 0.010) after 14 days from the injection. In conclusion, these results suggest that in acromegalic patients: (1) SR-L causes a rapid improvement in baseline cardiac function and in cardiopulmonary performance during exercise in acromegaly; (2) the endocrine (decrease in GH levels) and echocardiographic responses to SR-L are maximal after 7 days from the injection, whereas the effect of SR-L on the exercise performance are longer lasting.     

鲁登巴赫综合征的外科治疗

目的 :回顾分析 10例鲁登巴赫综合征 ,探讨该疾病在病理生理、诊断和治疗方面的特点。方法 :总结经外科治疗的鲁登巴赫综合征共 10例患者的临床资料。结果 :全组病例无围手术期死亡 ,无顽固性心力衰竭、肺动脉高压危象及恶性心律失常发生。结论 :鲁登巴赫综合征应及早手术治疗 ,修补房间隔缺损同时有效的解除二尖瓣狭窄 ,探查并处理合并的三尖瓣关闭不全 ,术后积极治疗肺动脉高压 ,支持心功能 ,可以取得满意的手术效果     

The distribution and severity of coronary artery disease and left ventricular dysfunction among patients with single coronary artery disease and angina pectoris

The distribution and severity of coronary artery disease and left ventricular dysfunction were evaluated in 103 patients with single coronary artery disease and angina pectoris. The coronary arterial patterns were separated into right (76), mixed (18), and left (9) systems depending upon the blood supply to the inferior surface of the left ventricle. The following relationships were noted: (1) In patients with single coronary artery disease and angina pectoris, coronary arterial lesions are similar among right, mixed, and left systems. (2) In order of frequency, single coronary artery disease occurred most commonly in the left anterior descending coronary artery (55), next most commonly in the right coronary artery (36), and least commonly in the circumflex/obtuse marginal coronary artery (12). (3) Left ventricular wall motion abnormalities were seen in descending order of frequency: patients with right coronary artery (50%), left anterior descending coronary artery (36%), and circumflex/obtuse marginal coronary artery (25%) disease.