Regional differences in LV collagen accumulation and mature cross-linking after myocardial infarction in rats

To determine the extent of and any regional differences in remodeling response of the extracellular matrix (ECM) to myocardial infarction (MI), moderate-to-large transmural infarcts were surgically produced in left ventricular (LV) free wall of rats. Animals were killed 13 wk after surgery. In comparison to age-matched controls, infarction was associated with an overall increase in heart weight, which included hypertrophy of both the right ventricle and LV. Although the remaining viable myocardium in LV free wall was significantly reduced, the interventricular septum was hypertrophied some 30% compared with control tissues (247 +/- 9 vs. 189 +/- 8 mg). Collagen concentration more than doubled in remaining viable free wall (8.92 +/- 0.59 vs. 3.95 +/- 0.25 mg/100 mg, P < 0.0001), and a smaller but still highly significant 27% increase occurred (P < 0.01) in the more remote septum. Degree of covalent cross-linking of collagen fibrils as assessed by hydroxylysylpyridinoline (HP) concentration also revealed regional differences in response of the ECM to infarction. Although HP concentration was increased 60% in viable free wall (P < 0.05) post-MI, it was unchanged in the septum. With respect to collagen characteristics of the transmural infarct per se, the scar exhibited still further increases in both collagen and HP concentrations compared with the already elevated values for these two parameters in viable free wall. The results indicate that any evaluation of the remodeling response of viable myocardium post-MI must include not only the myocyte but also the ECM, the principal component of which is collagen.

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Subacute Left Ventricular Free-Wall and Double Cardiac Rupture: Clinical Features and Surgical Considerations of a Surgically Salvageable Condition

Asian Cardiovascular and Thoracic Annals ◽

10.1177/021849239400200205 ◽

1994 ◽

Vol 2 (2) ◽

pp. 78-82

Author(s):

Harinder Singh Bedi ◽

Vijay Kumar Sharma ◽

Vijay Kohli ◽

Anil Mishra ◽

Ashok Jayant ◽

...

Keyword(s):

Myocardial Infarction ◽

Left Ventricle ◽

Cerebrovascular Accident ◽

Surgical Intervention ◽

Interventricular Septum ◽

Left Ventricular ◽

Cardiac Rupture ◽

Free Wall ◽

Review Of The Literature ◽

Left Ventricular Free Wall

Subacute cardiac rupture after myocardial infarction carries a high mortality. This article describes 4 cases—3 with rupture of the left ventricle and 1 with a combined rupture of the left ventricle and interventricular septum (double rupture). All patients were successfully operated; however, the patient with the double rupture died of a massive cerebrovascular accident on the 8th postoperative day. The importance of early diagnosis and prompt surgical intervention is discussed, along with a review of the literature.

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Myocardial infarction in rat eliminates regional heterogeneity of AP profiles, I to K+currents, and [Ca2+]i transients

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00518.2001 ◽

2002 ◽

Vol 283 (3) ◽

pp. H1157-H1168 ◽

Cited By ~ 36

Author(s):

Roger Kaprielian ◽

Rajan Sah ◽

Tin Nguyen ◽

Alan D. Wickenden ◽

Peter H. Backx

Keyword(s):

Myocardial Infarction ◽

Regional Differences ◽

Ventricular Myocytes ◽

Interventricular Septum ◽

Free Wall ◽

Right Ventricular Free Wall ◽

Regional Heterogeneity ◽

Intracellular Ca ◽

The Right ◽

K Currents

Transient outward K+ current density ( I to) has been shown to vary between different regions of the normal myocardium and to be reduced in heart disease. In this study, we measured regional changes in action potential duration (APD), I to, and intracellular Ca2+ concentration ([Ca2+]i) transients of ventricular myocytes derived from the right ventricular free wall (RVW) and interventricular septum (SEP) 8 wk after myocardial infarction (MI). At +40 mV, I to density in sham-operated hearts was significantly higher ( P < 0.01) in the RVW (15.0 ± 0.8 pA/pF, n = 47) compared with the SEP (7.0 ± 1.1 pA/pF, n = 18). After MI, I to density was not reduced in SEP myocytes but was reduced ( P < 0.01) in RVW myocytes (8.7 ± 1.0 pA/pF, n = 26) to levels indistinguishable from post-MI SEP myocytes. These changes in I to density correlated with Kv4.2 (but not Kv4.3) protein expression. By contrast, Kv1.4 expression was significantly higher in the RVW compared with the SEP and increased significantly after MI in RVW. APD measured at 50% or 90% repolarization was prolonged, whereas peak [Ca2+]i transients amplitude was higher in the SEP compared with the RVW in sham myocytes. These regional differences in APD and [Ca2+]i transients were eliminated by MI. Our results demonstrate that the significant regional differences in I to density, APD, and [Ca2+]i between RVW and SEP are linked to a variation in Kv4.2 expression, which largely disappears after MI.

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Sequential rupture of the left ventricular free wall and of the interventricular septum after myocardial infarction. Surgical implications

International Journal of Cardiology ◽

10.1016/0167-5273(88)90211-2 ◽

1988 ◽

Vol 21 (2) ◽

pp. 105-110 ◽

Cited By ~ 3

Author(s):

Bartolo Zingone ◽

Erika Della Grazia ◽

Aniello Pappalardo ◽

Bernardo Benussi ◽

Roberto Prandi ◽

...

Keyword(s):

Myocardial Infarction ◽

Interventricular Septum ◽

Left Ventricular ◽

Ventricular Free Wall ◽

Free Wall ◽

Left Ventricular Free Wall

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Losing Regulation of the Extracellular Matrix is Strongly Predictive of Unfavorable Prognostic Outcome after Acute Myocardial Infarction

International Journal of Molecular Sciences ◽

10.3390/ijms21176219 ◽

2020 ◽

Vol 21 (17) ◽

pp. 6219

Author(s):

Pei-Hsun Sung ◽

Kun-Chen Lin ◽

Han-Tan Chai ◽

John Y. Chiang ◽

Pei-Lin Shao ◽

...

Keyword(s):

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Left Ventricular ◽

Heart Weight ◽

Lung Injury Score ◽

Opposite Pattern ◽

Knock Out ◽

Group 4 ◽

Prognostic Outcome ◽

Group 3

This study tested the hypothesis that MMP-9−/−tPA−/− double knock out (i.e., MTDKO) plays a crucial role in the prognostic outcome after acute myocardial infarction (AMI by ligation of left-coronary-artery) in MTDKO mouse. Animals were categorized into sham-operated controls in MTDKO animals (group 1) and in wild type (B6: group 2), AMI-MTDKO (group 3) and AMI-B6 (group 4) animals. They were euthanized, and the ischemic myocardium was harvested, by day 60 post AMI. The mortality rate was significantly higher in group 3 than in other groups and significantly higher in group 4 than in groups 1/2, but it showed no difference in the latter two groups (all p < 0.01). By day 28, the left-ventricular (LV) ejection fraction displayed an opposite pattern, whereas by day 60, the gross anatomic infarct size displayed an identical pattern of mortality among the four groups (all p < 0.001). The ratio of heart weight to tibial length and the lung injury score exhibited an identical pattern of mortality (p < 0.01). The protein expressions of apoptosis (mitochondrial-Bax/cleaved-caspase3/cleaved-PARP), fibrosis (Smad3/T-GF-ß), oxidative stress (NOX-1/NOX-2/oxidized-protein), inflammation (MMPs2,9/TNF-α/p-NF-κB), heart failure/pressure overload (BNP/ß-MHC) and mitochondrial/DNA damage (cytosolic-cytochrome-C/γ-H2AX) biomarkers displayed identical patterns, whereas the angiogenesis markers (small vessel number/CD31+cells in LV myocardium) displayed opposite patterns of mortality among the groups (all p < 0.0001). The microscopic findings of fibrotic/collagen deposition/infarct areas and inflammatory cell infiltration of LV myocardium were similar to the mortality among the four groups (all p < 0.0001). MTDKO strongly predicted unfavorable prognostic outcome after AMI.

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A Case of Early Developed Left Ventricular Free Wall Rupture Followed by Acute Inferior Myocardial Infarction

Korean Circulation Journal ◽

10.4070/kcj.1999.29.1.73 ◽

1999 ◽

Vol 29 (1) ◽

pp. 73 ◽

Cited By ~ 1

Author(s):

Seung Chul Park ◽

Jae Han Kim ◽

Young Min Kim ◽

Sun Young Kwak ◽

Buyng Ok Yoon ◽

...

Keyword(s):

Myocardial Infarction ◽

Left Ventricular ◽

Ventricular Free Wall ◽

Free Wall ◽

Inferior Myocardial Infarction ◽

Left Ventricular Free Wall ◽

Free Wall Rupture ◽

Acute Inferior Myocardial Infarction

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Inhibition and reversal of myocardial infarction-induced hypertrophy and heart failure by NHE-1 inhibition

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00602.2003 ◽

2004 ◽

Vol 286 (1) ◽

pp. H381-H387 ◽

Cited By ~ 50

Author(s):

Ling Chen ◽

Chang Xun Chen ◽

Xiaohong Tracey Gan ◽

Norbert Beier ◽

Wolfgang Scholz ◽

...

Keyword(s):

Myocardial Infarction ◽

Heart Failure ◽

Infarct Size ◽

Treatment Delay ◽

Left Ventricular ◽

Heart Weight ◽

Coronary Artery Ligation ◽

Treatment Protocols ◽

Beneficial Effects ◽

All Treatment

Sodium/hydrogen exchange (NHE) inhibitors show promise as potential therapeutic agents for the treatment of heart failure, but it is not known whether they can reverse the maladaptive remodeling that results in heart failure. We sought to determine the effect of the NHE-1-specific inhibitor EMD-87580 (EMD) on heart failure produced by myocardial infarction in the rat and to assess whether up to 4 wk of treatment delay results in beneficial effects. Male Sprague-Dawley rats were subjected to coronary artery ligation (or a sham procedure) and followed for up to 3 mo, at which time hypertrophy and hemodynamics were determined. EMD was provided in the diet, and treatment commenced immediately or 2–4 wk after ligation. EMD significantly reduced hemodynamic abnormalities, including the elevation in left ventricular end-diastolic pressure, and diminished the loss of systolic function with all treatment protocols. Left ventricular dilatation and hypertrophy, as assessed by heart weight, cell size, and atrial natriuretic peptide (ANP) expression, were similarly reversed to sham or near-sham levels. In addition, the increased plasma ANP and pro-ANP values were reversed to levels not significantly different from sham. Surprisingly, virtually all beneficial effects were identical with all treatment protocols. These effects were observed in the absence of infarct size reduction or blood pressure-lowering effects. Our results suggest that NHE-1 inhibition attenuates and reverses postinfarction remodeling and heart failure with a treatment delay of up to 4 wk after infarction. The effect is independent of infarct size or afterload reduction, indicating a direct effect on the myocardium.

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Transcatheter closure of ventricular septal rupture with prolonged support of intra-aortic balloon pump after primary PCI: a case report

BMC Cardiovascular Disorders ◽

10.1186/s12872-021-02392-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Chuan Yang ◽

Yong Sun ◽

Deling Zou ◽

Zhaoqing Sun ◽

Xinzhong Zhang ◽

...

Keyword(s):

Myocardial Infarction ◽

Transcatheter Closure ◽

Interventricular Septum ◽

Left Ventricular ◽

Left Ventricular Ejection ◽

Drug Eluting Stent ◽

Ventricular Septal Rupture ◽

Total Occlusion ◽

Ventricular Ejection Fraction ◽

Intra Aortic Balloon Pump

Abstract Background Ventricular septal rupture (VSR) is a rare but severe complication of acute myocardial infarction (AMI). For such cases, surgical repair is recommended by major guidelines, but not always possible for such cases. Case presentation A 72-year-old man presented to the emergency room. ECG showed the ST-segment was elevated by 2–3 mm in lead II, III, and aVF, with Q-waves. Coronary angiography (CAG) showed multi-vessel disease with a total occlusion of the right coronary artery (RCA) and severe stenosis of the left anterior descending artery (LAD). A diagnosis of acute inferior myocardial infarction was made. VSR occurred immediately after percutaneous coronary intervention (a 2.5 × 20 mm drug-eluting stent implanted in RCA), and the patient developed cardiogenic shock. An intra-aortic balloon pump (IABP) was used to stabilize the hemodynamics. Transthoracic echocardiography (TTE) revealed an 11.4-mm left-to-right shunt in the interventricular septum. An attempt was made to reduce the IABP augmentation ratio for weaning on day 12 but failed. Transcatheter closure was conducted using a 24-mm double-umbrella occluder on day 28. The patient was weaned from IABP on day 31 and underwent secondary PCI for LAD lesions on day 35. The patient was discharged on day 41. Upon the last follow-up 6 years later, CAG and TTE revealed no in-stent restenosis, no left-to-right shunt, and 51% left ventricular ejection fraction. Conclusions Prolonged implementation of IABP can be a viable option to allow deferred closure of VSR in AMI patients, and transcatheter closure may be considered as a second choice for the selected senior and vulnerable patients, but the risk is still high.

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Successful Surgical Treatment of Postinfarction Rupture of Left Ventricular Myocardium

Russian Sklifosovsky Journal Emergency Medical Care ◽

10.23934/2223-9022-2020-9-1-140-147 ◽

2020 ◽

Vol 9 (1) ◽

pp. 140-147

Author(s):

M. K. Mazanov ◽

N. I. Kharitonova ◽

A. A. Baranov ◽

S. Yu. Kambarov ◽

N. M. Bikbova ◽

...

Keyword(s):

Myocardial Infarction ◽

Left Ventricle ◽

Surgical Intervention ◽

Ventricular Myocardium ◽

Left Ventricular ◽

Left Ventricular Myocardium ◽

Free Wall ◽

Fatal Complication ◽

Widespread Availability ◽

Complications Of Myocardial Infarction

ABSTRACT. The rupture of the left ventricle free wall is one of the most dangerous complications of myocardial infarction. Due to the widespread availability of echocardiography method, the detection of this fatal complication and the number of lives saved after surgery grew. The survival of patients depends on early diagnosis, stabilization of the patient’s condition, promptness and tactics of surgical intervention. We report a case of successful closure of a rupture of the left ventricle free wall on the 15th day after myocardial infarction.

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