Humans ; Myocardial Infarction ; pathology ; physiopathology ; Thrombosis ; pathology ; physiopathology

In order to evaluate the left ventricular remodeling in patients with myocardial infarction after revascularization with intravenous real-time myocardial contrast echocardiography (RT-MCE), intravenous RT-MCE was performed on 20 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions: homogeneous opacification=1; partial or reduced opaciflcation or subendocardial contrast defect=2; constrast defect=3. Myocardial perfusion score index (MPSI) was calculated by dividing the total sum of contrast score by the total number of segments with abnormal wall motion. Twenty patients were classified into 2 groups according to the MPSI: MPSImyocardial perfusion, MPSI>1.5 as poor myocardial perfusion. To assess the left ventricular remodeling, the following comparisons were carried out: (1) Comparisons of left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV) before and 3 months after revascularization in two groups; (2) Comparisons of LVEF, LVESV and LVEDV pre-revascularization between two groups and comparisons of these 3 months post-revascularization between two groups; (3) Comparisons of the differences in LVEF, LVESV and LVEDV between 3 months post-and pre-revascularization (DeltaLVEF, DeltaLVESV and DeltaLVEDV) between two groups; (4) The linear regression analysis between DeltaLVEF, DeltaLVESV, DeltaLVEDV and MPSI. The results showed that the LVEF obtained 3 months after revascularization in patients with MPSI>1.5 was obviously lower than that in those with MPSI1.5 was obviously larger than that in those with MPSI1.5 and those with MPSImyocardial infarction after revascularization.
Echocardiography/*methods ; Infusions, Intravenous ; Myocardial Infarction/*diagnosis ; Myocardial Infarction/pathology ; Myocardial Infarction/*ultrasonography ; Myocardial Reperfusion ; Myocardium/*pathology ; Perfusion ; Regression Analysis ; Time Factors ; Ventricular Remodeling

Sympathetic remodeling after myocardial infarction is presented as denervation, sympathetic nerve sprouting and sympathetic hyperinnervation, and is closely related to ventricular tachyarrhythmias and even sudden cardiac death at convalescence in patients with myocardial infarction. This article reviews the anatomic structure, morphology and functional remodeling of cardiac sympathetic nerve, as well as its role in healed myocardial infarction identification, which may provide references for forensic research.
Atrial Remodeling ; Forensic Sciences ; Heart ; Humans ; Myocardial Infarction/pathology*

To elucidate the mechanism of arrhythmia in healed myocardial infarction (HMI), the changes of action potential duration (APD), transient outward potassium current (Ito), delayed rectifier potassium current (IK) and inward rectifier potassium current (IK1) of left ventricular myocytes in non-infarcted zone of HMI were investigated. Rabbits were randomly assigned into two groups: HMI group, in which animals were subjected to thoracotomy and ligation of the circumflex coronary and sham-operated group, in which rabbits underwent thoracotomy but no conorary ligation. 3 months after the operation, the whole myocyte patch clamp technique was used to record APD, Ito, IK, and IK1 of ventricular myocytes in non-infarcted zone. Our results showed that the membrane capacitance was larger in HMI group than in sham-operated group. Action potential duration was significantly lengthened in HMI group and early afterdepolarization (EAD) appeared in HMI group. The densities of Ito, I(K, tail), and IK1 were reduced significantly in HMI group, from 6.72 +/- 0.42 pA/pF, 1.54 +/- 0.13 pA/pF and 25.6 +/- 2.6 pA/pF in sham-operated group to 4.03 +/- 0.33 pA/pF, 1.14 +/- 0.11 pA/pF and 17.6 +/- 2.3 pA/pF, respectively. It is concluded that the reduced densities of Ito, I(K, tail) and IK1 in ventricular myocytes of non-infarcted zone in HMI were responsible for the prolongation of APD and the presentation of EAD which played important roles in the development of malignant arrhythmia in HMI.
Action Potentials ; Arrhythmia/*etiology ; Heart Ventricles/metabolism ; Myocardial Infarction/complications ; Myocardial Infarction/metabolism ; Myocardial Infarction/*pathology ; Myocytes, Cardiac/*cytology ; Patch-Clamp Techniques ; Potassium Channels/*metabolism

Electrocardiography ; Humans ; Male ; Middle Aged ; Myocardial Bridging ; complications ; Myocardial Infarction ; etiology ; Myocardium ; pathology

Although coronary atherosclerosis occupies more than 90% of myocardial infarctions, anomalous coronary arteries are a potential cause of myocardial ischemia resulting in arrhythmia, angina, infarction, and sudden death. A medico-legal autopsy conducted on a 22 year-old healthy man who died suddenly after exercise, revealed that the right coronary artery ostium was situated higher the aortic ridge (sinotubular junction) with acute downward angulation of the proximal right coronary artery. There was no evidence of any other disease process. Coronary artery anomalies may be overlooked or misssed by the examining forensic pathologist. We described the pathology of this condition and briefly reviewed.
Arrhythmias, Cardiac ; Autopsy ; Coronary Artery Disease ; Coronary Vessels ; Death, Sudden* ; Humans ; Infarction ; Myocardial Infarction ; Myocardial Ischemia ; Pathology ; Young Adult

The myocardial viability after myocardial infarction was evaluated by intravenous myocardial contrast echocardiography. Intravenous real-time myocardial contrast echocardiography was performed on 18 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Viable myocardium was defined by evident improvement of segmental wall motion 3 months after coronary revascularization. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions: homogeneous opacification; partial or reduced opaciflcation or subendocardial contrast defect; contrast defect. The former two conditions were used as the standard to define the viable myocardium. The results showed that 109 abnormal wall motion segments were detected among 18 patients with myocardial infarction, including 47 segments of hypokinesis, 56 segments of akinesis and 6 segments of dyskinesis. The wall motion of 2 segments with hypokinesis before coronary revascularization which showed homogeneous opacification, 14 of 24 segments with hypokinese and 20 of 24 segments with akinese before coronary revascularization which showed partial or reduced opaciflcation or subendocardial contrast defect was improved 3 months after coronary revascularization. In our study, the sensitivity and specificity of evaluation of myocardial viability after myocardial infarction by intravenous real-time myocardial contrast echocardiography were 94.7% and 78.9%, respectively. It was concluded that intravenous real-time myocardial contrast echocardiography could accurately evaluate myocardial viability after myocardial infarction.
Angioplasty, Transluminal, Percutaneous Coronary ; Cell Survival ; Coronary Artery Bypass ; Echocardiography/*methods ; Models, Statistical ; Myocardial Infarction/*pathology ; Myocardial Infarction/*ultrasonography ; Myocardial Revascularization ; Myocardium/*pathology ; Perfusion ; Time Factors

Autopsy ; Female ; Heart Failure ; etiology ; pathology ; Humans ; Infant ; Myocardial Infarction ; etiology ; pathology ; Vascular Calcification ; complications ; pathology

OBJECTIVETo analyze the components of retrieved materials from the culprit lesion in ST-segment elevation myocardial infarction (STEMI) patients by manual aspiration during primary percutaneous coronary intervention (PCI).

METHODSVisible retrieved materials were collected, fixed in formalin and processed for paraffin embedding, sectioned and stained with hematoxylin and eosin (HE). The retrieved materials were microscopically divided into erythrocyte-rich thrombi, platelet/fibrin-rich thrombi, combined thrombi (similar proportions of erythrocytes and platelet/fibrin components), atherosclerotic plaque materials and edematous components. Based on pathological findings, thrombus materials were classified into fresh (< 1 d), lytic (1-5 d), fresh/lytic and organized thrombi (> 5 d) after formation. All patients were further classified into plaque positive and plaque negative groups. Clinical and angiographic data were also obtained for analyzing possible association between pathological findings and surrogates of myocardial reperfusion, including myocardial blush grade (MBG), enzymatic estimated infarction size (peak CK and CK-MB levels), left ventricular end diastolic diameter (LVEDD) and left ventricular ejection fraction (LVEF) which were assessed 16 h after procedure.

RESULTSVisible samples were collected from 49 patients by manual catheter aspiration (thrombus components in 46 patients, atherosclerotic plaque only in 3 patients). Frequency of erythrocyte-rich thrombi, platelet/fibrin-rich thrombi and combined thrombi were 41.3% (19/46), 30.4% (14/46) and 28.2% (13/46), respectively. The incidence of fresh, lytic, fresh/lytic and organized thrombi were 47.8% (22/46), 32.6% (15/46), 10.9% (5/46) and 8.7% (4/46), respectively. Plaque materials were found in 57.1% (28/49) patients, including ruptured plaque accompanied by thrombus formation [8.2% (4/49)], fibrous plaque [6.1% (3/49)] and thickened intima [2.0% (1/49)]. Baseline characteristics did not differ between plaque positive (n = 28) and plaque negative (n = 21) groups. Ratios of MBG 3 were higher in plaque positive group than in plaque negative group [82.1% (23/28) vs. 52.4% (11/21), P = 0.025]. Peak CK and CK-MB levels were lower in the former than in the later [(1705 +/- 1647) U/L vs. (2629 +/- 2013) U/L, P = 0.042; (146 +/- 136) microg/L vs. (258 +/- 215) microg/L, P = 0.016; respectively]. Furthermore, LVEF were higher in plaque positive group than in plaque negative group (0.59 +/- 0.10 vs. 0.52 +/- 0.08, P = 0.012).

CONCLUSIONManual catheter aspiration during primary PCI in STEMI patients is an effective way for removing thrombus and plaque materials, and plaque debulking before stenting or pre-dilation and this procedure might probably improve myocardial reperfusion, limit infarction size and improve cardiac function.

Aged ; Angioplasty, Balloon, Coronary ; Coronary Vessels ; pathology ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; pathology ; surgery ; Myocardial Reperfusion ; methods ; Suction

OBJECTIVETo investigate the myocardial proliferation/regeneration capacities at different time points and at different parts of the heart post acute myocardial infarction (AMI) in rats.

METHODSA total of 64 adult Sprague-Dawley (SD) rats were randomly divided into AMI group (left anterior descending coronary ligation, n = 44) and sham-operated group (n = 20). Rats were sacrificed on day 3, 5, 7, 14 and 60 respectively post operation (n = 5-9 at each time point) and ventricular tissues were harvested. 5-Bromo-2-deoxyUridine (Brdu, 50 mg/kg) was injected intraperitoneally at 12 and 24 hours before sacrifice. Morphological and pathological changes of the myocardium were observed after HE staining. Brdu-positive and c-kit and Brdu double-positive cardiomyocytes were analyzed post immunohistochemistry and immunofluorescence staining. Striated structure of new cells was detected by PTAH staining. Alpha-sarcomeric actin antibody was used to identify new cardiomyocytes.

RESULTBrdu-positive cardiomyocytes at border zone and non-ischemic zone were significantly increased at 5 days post AMI and peaked at 7th day post operation (Border zone, AMI: 1.26% ± 0.15% vs.Sham: 0.22% ± 0.06%, P < 0.01; right ventricle, AMI: 0.75% ± 0.12% vs.Sham: 0.18% ± 0.07%, P < 0.01). There was no significant difference between the two groups on the 60th post-operation day. Brdu-positive cells were 1.7-fold higher in infarct border zone than in the right ventricular area of AMI rats on the 7th post operation day (1.26% ± 0.15%, vs.0.75% ± 0.12%, P < 0.01) and was 1.4-fold higher on the 14th post operation day (0.77% ± 0.09%, vs.0.54% ± 0.11%, P < 0.01). PTAH staining evidenced myocardial striated structure inside the new cells. Immunofluorescent assay showed that parts of Brdu positive cells were myocardial actin positive, and the c-kit and Brdu double-positive myocardial cells were also observed. Most nuclei of tehse new cardiomyocytes were small and round-shaped.

CONCLUSIONSMyocardial proliferation/regeneration increased significantly after AMI in rats, especially around the infarct border zone. The myocardial proliferation/regeneration was time-dependent. Parts of the new cardiomyocytes had some characteristics of cardiac stem cells. This study suggests that myocardial proliferation/regeneration may be activated after acute myocardial injury.

Animals ; Cell Proliferation ; Male ; Myocardial Infarction ; pathology ; Myocytes, Cardiac ; pathology ; Rats ; Rats, Sprague-Dawley ; Regeneration