Dark-Blood Delayed Enhancement Cardiac Magnetic Resonance of Myocardial Infarction

Objectives

This study introduced and validated a novel flow-independent delayed enhancement technique that shows hyperenhanced myocardium while simultaneously suppressing blood-pool signal.

Multi-Ethnic Study of Atherosclerosis (MESA): JACC Focus Seminar 5/8

The MESA (Multi-Ethnic Study of Atherosclerosis) is a National Heart, Lung, and Blood Institute–sponsored prospective study aimed at studying the prevalence, progression, determinants, and prognostic significance of subclinical cardiovascular disease in a sex-balanced, multiethnic, community-dwelling U.S. cohort. MESA helped usher in an era of noninvasive evaluation of subclinical atherosclerosis presence, burden, and progression for the evaluation of atherosclerotic cardiovascular disease risk, beyond what could be predicted by traditional risk factors alone. Concepts developed in MESA have informed international patient care guidelines, providing new tools to effectively guide public health policy, population screening, and clinical decision-making. MESA is grounded in an open science model that continues to be a beacon for collaborative science. In this review, we detail the original goals of MESA, and describe how the scope of MESA has evolved over time. We highlight 10 significant MESA contributions to cardiovascular medicine, and chart the path forward for MESA in the year 2021 and beyond.     

Acute myocardial infarction during streptokinase therapy

A 45-year-old man developed sequential inferolateral and anterior myocardial infarctions within 10 hours of a possible allergic reaction to oral penicillin. The anterior myocardial infarction occurred during apparently successful streptokinase therapy for the initial inferolateral infarction. Subsequent coronary arteriography confirmed a subtotal stenosis of the left circumflex coronary artery and a complete thrombotic occlusion of the left anterior descending artery. This case documents the occurrence of three rare clinical phenomena; first, the occurrence of sequential acute myocardial infarctions in close temporal proximity; second, the occurrence of myocardial infarction during thrombolytic therapy; and third, the association of myocardial infarction with a possible allergic reaction.     

急性心肌梗死冠状动脉内血栓溶解治疗与再灌注性心律失常

２２例急性心肌梗死患者接受经皮冠状动脉内血栓溶解治疗，经即刻冠状动脉造影证实１４例冠状动脉再通。９例（６４．３％）发生再灌注性心律失常（ＲＡ）。１４例中７例（５０．０％）为室性ＲＡ，３例（２１．４％）发生加速性室性自主节律，后者为提示再灌注的特异性较高的指标。一过性缓慢性心律失常的５例（３５．８％）均发生在下壁及（或）后壁梗死。ＲＡ的发生与再灌注前心肌缺血时间和缺血性心律失常存在与否无关，心肌功能严重受损患者可能更易发生ＲＡ。本文并就如何预防和治疗ＲＡ进行了探讨。     

Short- and long-term prognostic importance of complete bundle-branch block complicating acute myocardial infarction

Among 1013 consecutive patients with acute myocardial infarction (AMI), 104 (10%) developed complete bundle-branch block (BBB). The clinical characteristics and the short- and long-term prognosis were similar in the 53 patients with right and the 51 patients with left BBB. Compared to the 909 patients without this conduction disturbance, these 104 patients were older (64 +/- 9 vs. 58 +/- 10 years, p less than 0.001), more frequently women (26 vs. 17%, p less than 0.05), had a larger infarct (peak CK 1672 +/- 1124 vs. 1356 +/- 1089 IU/l, p less than 0.001), more frequently anterior (60 vs. 37%, p less than 0.001). They had a higher incidence of Killip class greater than 1 (63 vs. 38%, p less than 0.001), pericarditis (40 vs. 23%, p less than 0.001), atrial fibrillation or flutter (22 vs. 12%, p less than 0.01), ventricular fibrillation (15 vs. 9%, p less than 0.05), and atrioventricular block (23 vs. 11%, p less than 0.001). Both hospital mortality (32 vs 10%, p less than 0.001) and 3-year posthospital mortality (37 vs. 18%, p less than 0.001) were much higher among patients with complete BBB. Transient BBB had the same deleterious prognosis as BBB persistent at discharge (mortality 33 vs. 39%, NS). The prognostic importance of BBB was more prominent during the first 6 months after infarction (mortality between 6 and 36 months: 18% with BBB vs. 11% without BBB, NS).     

高龄和年轻冠心病患者冠状动脉介入治疗临床对比分析

目的探讨高龄和年轻冠心病患者冠状动脉介入治疗效果。方法选择在我科行冠状动脉介入治疗的冠心病患者320例,根据年龄分为年轻组(146例)、高龄组(62例)和对照组(112例),分析各组患者临床特点、病变特点及介入治疗效果。结果以急性心肌梗死起病的患者在年轻组、高龄组和对照组分别占45.2%,17.7%和23.2%(P=0.000);以心绞痛起病的患者中1周内发生心肌梗死的患者分别占47.2%、14.3%和40.0%(P=0.018);非ST段抬高心肌梗死的发生率分别为1.9%、10.5%和1.9%(P=0.000);高血压患者在3组中分别占40.4%、67.7%和56.3%(P=0.001);吸烟患者分别占71.2%、22.6%和55.4%(P=0.000);肾功能不全患者分别占1.4%、16.1%和2.7%(P=0.000);住院病死率分别占0、6.5%和0.9%(P=0.003)。结论年轻患者多以急性心肌梗死起病;高龄患者病变复杂,合并多系统疾病多,严重并发症发生率偏高。     

缺血预适应与后适应叠加对老年急性心肌梗死急症介入治疗后的影响

目的研究梗死前心绞痛(缺血预适应)与缺血后适应叠加对老年急性心肌梗死患者介入治疗后冠状动脉血流速度及预后的影响。方法选取12h内接受急症冠状动脉介入治疗的心肌梗死患者106例,35例有梗死前心绞痛症状并接受缺血后适应者为预适应与后适应叠加组(IPC+Postcon),37例单纯接受缺血后适应干预者为后适应组(Postcon),其余34例为单纯再灌注组(IR),测定校正TIMI帧数(CTFC)、血肌酸磷酸激酶(CK)、肌酸磷酸激酶同工酶(CK-MB)、丙二醛,术后8w测定室壁运动记分。结果IPC+Postcon组与Postcon组CTFC明显快于IR组(27.12±5.84,26.98±5.76vs.31.53±7.41,P<0.05),CK峰值与CK-MB峰值明显低于IR组(1243.35±801.31U/L,1238.67±817.26U/Lvs.1697.76±965.63U/L,P<0.05;120.97±78.28U/L,117.94±75.81U/Lvs.174.45±92.67U/L,P<0.05),IPC+Postcon组与Postcon组间无统计学差异;3组患者入院时MDA均高于对照组,术后各时点IPC+Postcon组与Postcon组均低于IR组。术后8wIPC+Postcon组与Postcon组室壁运动恢复优于IR组(1.16±0.12,1.17±0.11vs.1.31±0.15,P<0.05)。结论缺血后适应与预适应一样可以改善介入治疗后冠状动脉血流速度,减少自由基的生成,改善心功能。预适应与后适应叠加对上述功能的改善并无增强作用。     

参脉注射液治疗老年非ST段抬高心肌梗死急性期的疗效观察

目的探讨参脉注射液对老年非趼段抬高心肌梗死（NSTEMI）急性期的疗效及作用机制。方法68例老年急性非ST段抬高心肌梗死病人随机分为两组，除常规心肌梗死治疗外，参脉组每天静脉注射30mL参脉，刺五加组每矢静脉注射刺五加400mg．疗程4周，于用药前后监测心肌酶、心电图与血液流变学等指标。结果参脉组总有效率91．2％，显著高于刺五加组（80．0％），在降低心肌酶、改善心电图及血液流变学方面的作用均优于刺五加组（P〈0．01）。结论参脉注射液对老年非ST段抬高心肌梗死急性期的治疗效果好，副反应少，临床疗效显著。     

经皮冠状动脉介入治疗对急性心肌梗死患者左室重构的影响

经皮冠状动脉介入治疗能够有效防止左室重构 ,改善左室功能 ,但其作用机制和实行时机尚不明确。通过对其作用机制及实行时机的研究 ,为及时、有效实行PCI提供理论依据。     

Effect of verapamil on systolic and diastolic coronary blood flow velocity in asymptomatic and mildly symptomatic patients with hypertrophic cardiomyopathy

OBJECTIVE: To assess non-invasively the effect of verapamil treatment on coronary blood flow velocity in asymptomatic and mildly symptomatic patients with hypertrophic cardiomyopathy. DESIGN: High frequency transthoracic Doppler echocardiography was used to compare resting phasic coronary blood flow velocity before and after a one month period of verapamil treatment in 17 patients (14 men and three women) with non-obstructive hypertrophic cardiomyopathy. Eighteen healthy subjects formed an age and sex matched control group. Systolic and diastolic coronary blood flow velocity was measured in the distal portion of left anterior descending coronary artery using high frequency transthoracic Doppler echocardiography. Blood flow velocity before and after verapamil was compared in the patients with cardiomyopathy and with the results in the control group. RESULTS: Compared with the controls, patients with hypertrophic cardiomyopathy had increased diastolic coronary blood flow velocity (41.8 (8.1) v 59.9 (21.9) cm/s, p < 0.01) and a lower mean systolic coronary blood flow velocity (18.7 (10.8) v -11.2 (27.5) cm/s, p < 0. 01) before verapamil treatment. A backward pattern of systolic flow, manifested by negative values of coronary blood flow velocity, was recorded in eight of the patients, while no negative values were found in the controls. After verapamil treatment the retrograde systolic blood flow was restored to an anterograde pattern in only one patient. The mean value of systolic coronary blood flow velocity did not change significantly and remained lower than the systolic forward flow velocity in the controls (-3.6 (31.8) v 18.7 (10.8) cm/s, p < 0.05). However, diastolic coronary blood flow velocity decreased significantly after verapamil (59.9 (21.9) v 50.7 (19.5) cm/s p < 0.05), reaching a level comparable with that in the controls (50.7 (19.5) v 41.8 (8.1) cm/s, p > 0.05). CONCLUSIONS: In contrast to healthy subjects, in non-obstructive hypertrophic cardiomyopathy the systolic pattern of coronary blood flow was heterogeneous (both retrograde and anterograde), and diastolic coronary blood flow velocity was abnormally increased, despite a lack of significant symptoms. Verapamil treatment did not restore the forward pattern of systolic blood flow but decreased diastolic blood flow velocity to a level comparable with that in healthy subjects.