Feasibility of identifying viable myocardium in rest and stress magnetic resonance imaging (MRI) was evaluated using 3 hr occlusion and 30 min reperfusion model of left anterior descending (LAD) coronary artery in 12 felines. At rest MRI, viable myocardium confirmed by 2,3,5-triphenyl tetrazolium chloride (TTC)- staining showed rapid signal intensity (SI) rise followed by gradual decline not significantly different from normal myocardium that the two hyperperfused regions were distinguishable only from the hypoperfused nonviable myocardium. At stress MRI, hyperemia induced perfusion change was most pronounced in normal myocardium with earlier and greater peak enhancement followed by brisk 'washout' phase while minimally augmented enhancement in viable myocardium was still in 'washin' phase. From these findings, it was concluded that viable myocardium is identified in rest and stress MRI as redistributing hypo- perfusion compared to persistent hyper-perfusion of the normal myocardium and the persistent hypo-perfusion of the nonviable myocardium.
Animal ; Cats ; Heart/*radiography ; Hyperemia/*radiography ; Magnetic Resonance Imaging ; Myocardial Infarction/*radiography ; Myocardial Reperfusion Injury/*radiography ; Stress

BACKGROUND AND OBJECTIVES: Poor R-wave progression (PRWP) is a common electrocardiographic diagnosis. However, the diagnostic usefulness of PRWP for coronary artery disease (CAD) and the plausible explanation for subjects with normal heart function are unclear. SUBJECTS AND METHODS: We included 20,739 subjects who had routine medical examinations and applied the commonly used criteria (R-waves in V3 or V4 < or =2 mm) and the Marquette criteria in the current study. Subjects with PRWP by the Marquette criteria, but with no evidence of specific causes, were identified. Healthy age- and gender-matched controls were selected randomly for comparing cardiothoracic ratios. RESULTS: The commonly used criteria in practice were met by 372 of the 20,739 subjects (1.8%). The Marquette criteria were met by 96 subjects (0.5%), and 82 of who agreed to medical evaluation. Five subjects had known CAD and only one subject was shown to have a silent myocardial infarction by additional testing. Therefore, the positive predictive value of PRWP for CAD was 7.3% (6/82) based on the Marquette criteria. As compared with the control group, the subjects with PRWP had a significantly low cardiothoracic ratio (0.425 vs. 0.445, p<0.05), especially among the male group (0.454 vs. 0.407, p=0.02). CONCLUSION: The positive predictive value of PRWP for CAD in the general population is so low that additional tests for diagnosis may be unreasonable. In addition, a low cardiothoracic ratio could be a plausible explanation of PRWP in subjects without any identifiable cause.
Coronary Artery Disease ; Electrocardiography ; Heart ; Humans ; Male ; Myocardial Infarction ; Prevalence ; Radiography, Thoracic

OBJECTIVE: To evaluate the usefulness of multidetector-row computed tomography (CT) in the evaluation of reperfused myocardial infarction. MATERIALS AND METHODS: Eleven rabbits were subjected to 90-min occlusion of the left anterior descending coronary artery followed by reperfusion. Multidetector-row CT was performed 31 hours+/-21 after the procedure and preand post-contrast multiphase helical CT images were obtained up to 10 min after contrast injection. The animals were sacrificed after 30 days and histochemical staining of the resected specimens was perfomed with 2'3'5-triphenyl tetrazolium chloride (TTC). RESULTS: In all 11 cases, the areas of myocardial infarction demonstrated with TTC-staining were identified on the CT images and the lesions showed hypoenhancement on the early phases up to 62 sec and hyperenhancement on the delayed phases of 5 min and 10 min compared with normal myocardial enhancement. The percentage area of the lesion with respect to the left ventricle wall on CT was significantly correlated with that of the TTC-staining results (p < 0.001 for both early and delayed phase CT) according to the generalized linear model analysis. The areas showing hypoenhancement on early CT were significantly smaller than those with hyperenhancement on delayed CT (p < 0.0001). CONCLUSION: Multidetector-row CT may be useful in the detection and sizing of reperfused myocardial infarction.
Animals ; Feasibility Studies ; Models, Animal ; Myocardial Infarction/*radiography ; Myocardial Reperfusion Injury/*radiography ; Rabbits ; Reproducibility of Results ; Support, Non-U.S. Gov't ; Tomography, Spiral Computed ; *Tomography, X-Ray Computed/methods

PURPOSE: The present study aimed to investigate the impact of high-sensitivity C-reactive protein (hs-CRP) and renal dysfunction on clinical outcomes in acute myocardial infarction (AMI) patients. MATERIALS AND METHODS: The study involved a retrospective cohort of 8332 patients admitted with AMI. The participants were divided into 4 groups according to the levels of estimated glomerular filtration rate (eGFR) and hs-CRP: group I, no renal dysfunction (eGFR > or =60 mL.min(-1).1.73 m(-2)) with low hs-CRP (< or =2.0 mg/dL); group II, no renal dysfunction with high hs-CRP; group III, renal dysfunction with low hs-CRP; and group IV, renal dysfunction with high hs-CRP. We compared major adverse cardiac events (MACE) over a 1-year follow-up period. RESULTS: The 4 groups demonstrated a graded association with increased MACE rates (group I, 8.8%; group II, 13.8%; group III, 18.6%; group IV, 30.1%; p<0.001). In a Cox proportional hazards model, mortality at 12 months increased in groups II, III, and IV compared with group I [hazard ratio (HR) 2.038, 95% confidence interval (CI) 1.450-2.863, p<0.001; HR 3.003, 95% CI 2.269-3.974, p<0.001; HR 5.087, 95% CI 3.755-6.891, p<0.001]. CONCLUSION: High hs-CRP, especially in association with renal dysfunction, is related to the occurrence of composite MACE, and indicates poor prognosis in AMI patients.
Aged ; C-Reactive Protein/*metabolism ; Coronary Angiography ; Female ; Humans ; Kidney/*physiopathology ; Male ; Middle Aged ; Myocardial Infarction/*metabolism/*radiography ; Retrospective Studies

PURPOSE: Coronary flow reserve (CFR) in the non-infarcted myocardium is often impaired following acute myocardial infarction (AMI). However, the clinical significance of CFR in the non-infarcted myocardium is not fully understood. The objective of the present study was to assess whether a relationship exists between CFR and left ventricular remodeling following AMI. MATERIALS AND METHODS: We enrolled 18 consecutive patients undergoing coronary intervention. Heart function was analyzed using real-time myocardial contrast echocardiography at one week and six months after coronary angioplasty. Ten subjects were enrolled as the control group and were examined using the same method at the same time to assess CFR. Cardiac troponin I (cTnI) levels were routinely analyzed to estimate peak concentration. RESULTS: CFR was 1.55+/-0.11 in the infarcted zone and 2.05+/-0.31 in the remote zone (p<0.01) at one week following AMI. According to CFR values in the remote zone, all patients were divided into two groups: Group I (CFR <2.05) and Group II (CFR >2.05). The levels of cTnI were higher in Group I compared to Group II on admission (36.40 vs. 21.38, p<0.05). Furthermore, left ventricular end diastolic volume was higher in Group I compared to Group II at six months following coronary angioplasty. CONCLUSION: Microvascular dysfunction is commonly observed in the remote myocardium. The CFR value accurately predicts adverse ventricular remodeling following AMI.
Aged ; Coronary Angiography ; Coronary Circulation/physiology ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction/*physiopathology/radiography ; Myocardium/*pathology ; Ventricular Remodeling/*physiology

PURPOSE: Coronary flow reserve (CFR) in the non-infarcted myocardium is often impaired following acute myocardial infarction (AMI). However, the clinical significance of CFR in the non-infarcted myocardium is not fully understood. The objective of the present study was to assess whether a relationship exists between CFR and left ventricular remodeling following AMI. MATERIALS AND METHODS: We enrolled 18 consecutive patients undergoing coronary intervention. Heart function was analyzed using real-time myocardial contrast echocardiography at one week and six months after coronary angioplasty. Ten subjects were enrolled as the control group and were examined using the same method at the same time to assess CFR. Cardiac troponin I (cTnI) levels were routinely analyzed to estimate peak concentration. RESULTS: CFR was 1.55+/-0.11 in the infarcted zone and 2.05+/-0.31 in the remote zone (p<0.01) at one week following AMI. According to CFR values in the remote zone, all patients were divided into two groups: Group I (CFR <2.05) and Group II (CFR >2.05). The levels of cTnI were higher in Group I compared to Group II on admission (36.40 vs. 21.38, p<0.05). Furthermore, left ventricular end diastolic volume was higher in Group I compared to Group II at six months following coronary angioplasty. CONCLUSION: Microvascular dysfunction is commonly observed in the remote myocardium. The CFR value accurately predicts adverse ventricular remodeling following AMI.
Aged ; Coronary Angiography ; Coronary Circulation/physiology ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction/*physiopathology/radiography ; Myocardium/*pathology ; Ventricular Remodeling/*physiology

BACKGROUNDLeft ventricular (LV) dyssynchrony has been described to occur in patients with myocardial infarction. Dyssynchrony of left ventricular mechanical contraction produces adverse hemodynamic consequences. This study aimed to test the capacity of geometric rebuilding by aneurysm plication to restore a more synchronous contractile pattern after a mechanical, rather than electrical, intervention.

METHODSA total of sixty patients with anterior myocardial infarction, QRS duration < 120 ms, electively undergoing operation between January 2008 and January 2010 were included for analysis. Real-time 3-dimensional echocardiography was performed to assess LV function, LV systolic and diastolic dyssynchrony by measuring ejection fraction (EF), peak ejection rate (PER), peak filling rate (PFR) and LV dyssynchrony. LV dyssynchrony was defined as the systolic dyssynchrony of the time to reach the minimum systolic volume for 16 LV segments, expressed in percent cardiac cycle, systolic dyssynchrony index (SDI). We compared changes of LV dyssynchrony at different interval times.

RESULTSLV contraction was significantly asynchronous because preoperative SDI was higher, EF, PER and PFR were lowered. Compared with function after operation, LV mechanical intraventricular resynchronization was improved with decreased SDI ((8.7 ± 0.5)% vs. (14.3 ± 1.6)%, P = 0.01); LV function was improved with EF increasing ((43 ± 9)% vs. (37 ± 7)%, P = 0.001), and LV systolic and diastolic dyssynchrony was improved with more rapid PFR (199.4 ± 15.6 vs. 148.4 ± 21.2, P = 0.002) and PER (212.4 ± 14.5 vs. 156.3 ± 26.2, P = 0.001).

CONCLUSIONSSystolic and diastolic dyssynchrony was highly prevalent in patients with aneurysm, irrespective of QRS duration. Aneurysm plication produces a mechanical intraventricular resynchronization.

Aged ; Aneurysm ; surgery ; Echocardiography, Three-Dimensional ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; diagnostic imaging ; surgery ; Radiography

Bronchial Arteries ; diagnostic imaging ; Embolization, Therapeutic ; methods ; Hemoptysis ; therapy ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; etiology ; Radiography

We report the case of a female who died of suspected acute myocardial infarction. Post-mortem CT angiography (PMCTA) was performed with intravascular contrast infusion before the standard autopsy, and it successfully demonstrated the complete thrombotic occlusion of a coronary artery and also a corresponding perfusion defect on myocardium. We herein describe the PMCTA findings of a cardiac death with special emphasis on the potential benefits of this novel CT technique in forensic practice.
*Autopsy ; Coronary Occlusion/*diagnosis/etiology/radiography ; Coronary Vessels/pathology/radiography ; Female ; Humans ; Middle Aged ; Myocardial Infarction/etiology/pathology ; Myocardium ; Thrombosis/complications/*diagnosis ; Tomography, X-Ray Computed

INTRODUCTIONWe report a case of neurogenic pulmonary oedema (NPO) following massive left cerebral infarct, which was initially misdiagnosed as acute myocardial infarction (AMI).

CLINICAL PICTUREThis 52-year-old man presented with acute loss of consciousness with normal brain computed tomography (CT). He was treated as non-ST-elevation AMI complicated with pulmonary oedema based on findings of chest radiograph (bilateral pulmonary oedema), electrocardiogram (marked ST-T changes in leads V3 to V6), and cardiac enzymes [elevated creatinine kinase (CK) and CK-MB]. However, coronary angiogram and serial cardiac enzymes were inconclusive. Anisocoria developed after admission and a repeat brain CT was evident for large left cerebral infarct.

TREATMENTDecompressive craniectomy was carried out.

OUTCOMEMortality.

CONCLUSIONSThe diagnosis of NPO can be challenging when it occurs without abnormal findings on preliminary brain CT. It can be mistaken for cardiogenic pulmonary oedema secondary to AMI.

Cerebral Infarction ; physiopathology ; Coma ; Diagnosis, Differential ; Diagnostic Errors ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; diagnosis ; Pulmonary Edema ; diagnosis ; physiopathology ; Radiography, Thoracic ; Taiwan