Ventricular free wall rupture following acute myocardial infarction

Biventricular Takotsubo syndrome complicated with cardiogenic shock and ventricular septal rupture: a case report

Background

Takotsubo syndrome (TTS) mimics acute coronary syndromes but can lead to serious cardiac complications, emphasizing the need for improved understanding and management.

Case summary

We describe a TTS case presented with cardiogenic shock due to ventricular septal rupture (VSR). Successful treatment involved mechanical circulatory support followed by VSR surgical closure.

Discussion

Ventricular septal rupture is the rarest and deadliest complication associated with TTS. Prompt recognition and a multidisciplinary approach are crucial to achieve the best possible outcome.

Successful conservative treatment for left ventricular free wall rupture after acute myocardial infarction

Left ventricular free wall rupture (LVFWR) is a rare but fatal complication of acute myocardial infarction (AMI). An 81-year-old female patient with several cardiovascular risk factors presented to the emergency department with symptoms of developing a chronic stomachache and cold sweat. An echocardiograph showed wall motion abnormalities from the lateral to posterior wall, as well as pericardial effusion containing clots of up to 17 mm in the posterior wall that indicated LVFWR after AMI. Although she was conscious after being brought to the initial care unit, she suddenly lost consciousness and fell into electromechanical dissociation (EMD). Endotracheal intubation was immediately initiated and her pericardial drainage and intra aortic balloon pump (IABP) placement, and hemodynamics recovered. Although she had 100% obstruction in the left circumflex artery (LCX) #12 on coronary angiography (CAG), she was discharged to the Intensive Care Unit (ICU) without percutaneous coronary intervention (PCI). Conservative treatment such as intubation, sedation, pericardiocentesis and strict blood pressure management as well as treatment by IABP long-term support led to the patient being uneventfully discharged after 60 days.

Cardiac rupture during acute myocardial infarction : Autopsy study (2004-2020)

INTRODUCTION

Cardiac rupture is a rare but critical complication of myocardial infarction with an incidence of 1 to 3% of cases. We aimed in this autopsy study to analyze the anatomical, epidemiological, cardiac, and coronary profiles of cardiac rupture in the Monastir region.

METHODS

We conducted a descriptive study with retrospective data collection of all cases of myocardial infarction complicated by a cardiac rupture over seventeen years (2004-2020).

RESULTS

Thirty-one cases were included in this study. The mean age of the cases was 67 years with a male predominance. Sixteen cases (57%) had cardiovascular risk factors. The most common symptomatology reported before death was acute chest pain in 57% of cases. Fourteen cases (45%) corresponded to the definition of sudden cardiac death. At autopsy, the heart had a mean weight of 452.78 grams. A large hemopericardium was associated in 90% of cases. Myocardial rupture involved the posterior wall of the left ventricle in 50% of cases. The myocardial rupture occurred at a site of acute myocardial infarction in 86% of cases and on a myocardial scar in 14% of cases. The coronary study showed double or triple vessel atherosclerotic coronary artery disease in 57% of cases with fresh thrombi at the infarct-related coronary in 11% of cases.

CONCLUSIONS

Our analysis found that cardiac rupture mostly involved elderly subjects with underlying cardiovascular risk factors. Our findings sustain that age is a determining prognostic factor after acute coronary syndrome with the need for further education and awareness-raising efforts to speed up access to care for these patients.

Acute Cardiac Emergencies

Acute cardiac emergencies are life threatening. The initial responses to acute cardiac emergencies must be rapid, efficient, skillful, and well-planned. The goal of this article is to provide information that can be used to facilitate the prompt recognition and treatment of the most common acute cardiac emergencies.

Cardiac mechanostructure: Using mechanics and anisotropy as inspiration for developing epicardial therapies in treating myocardial infarction

The mechanical environment and anisotropic structure of the heart modulate cardiac function at the cellular, tissue and organ levels. During myocardial infarction (MI) and subsequent healing, however, this landscape changes significantly. In order to engineer cardiac biomaterials with the appropriate properties to enhance function after MI, the changes in the myocardium induced by MI must be clearly identified. In this review, we focus on the mechanical and structural properties of the healthy and infarcted myocardium in order to gain insight about the environment in which biomaterial-based cardiac therapies are expected to perform and the functional deficiencies caused by MI that the therapy must address. From this understanding, we discuss epicardial therapies for MI inspired by the mechanics and anisotropy of the heart focusing on passive devices, which feature a biomaterials approach, and active devices, which feature robotic and cellular components. Through this review, a detailed analysis is provided in order to inspire further development and translation of epicardial therapies for MI.

Heart Rate Reduction with Ivabradine Prevents Cardiac Rupture after Myocardial Infarction in Mice

PURPOSE

Cardiac rupture is a fatal complication following myocardial infarction (MI). An increase in heart rate (HR) is reportedly an independent risk factor for cardiac rupture during acute MI. However, the role of HR reduction in cardiac rupture after MI remains to be fully elucidated. We aimed to evaluate the therapeutic efficacy of HR reduction with ivabradine (IVA) on post-MI cardiac rupture in mice.

METHODS

We induced MI in mice by ligating the left anterior descending coronary artery. Subsequently, we subcutaneously implanted osmotic pumps filled with IVA solution or vehicle (Veh) in the surviving MI mice at 24 h postoperatively. We biochemically analyzed the myocardium on day 5, additionally observed the mice for 10 days, and analyzed the rates of cardiac rupture and non-cardiac rupture death, and survival after MI.

RESULTS

HR was significantly lower in the IVA-treated mice, whereas blood pressure was comparable between the two groups. Compared to the Veh-treated mice, apoptosis was significantly reduced in the MI border zone in the IVA-treated mice. Although there were no differences in the infarct size of the surviving MI mice between the two groups, HR reduction with IVA significantly reduced cardiac rupture (rupture rate 26 and 8% in the Veh-treated and IVA-treated groups, respectively) and improved survival after MI.

CONCLUSION

Our findings suggest that HR reduction with IVA prevents cardiac rupture after MI. This may be particularly effective in MI patients with a high HR who are either unable to adequately tolerate β-blockers or whose HR remains high despite receiving β-blockers.

Acute Myocardial Infarction in Women: A Scientific Statement From the American Heart Association

Cardiovascular disease is the leading cause of mortality in American women. Since 1984, the annual cardiovascular disease mortality rate has remained greater for women than men; however, over the last decade, there have been marked reductions in cardiovascular disease mortality in women. The dramatic decline in mortality rates for women is attributed partly to an increase in awareness, a greater focus on women and cardiovascular disease risk, and the increased application of evidence-based treatments for established coronary heart disease. This is the first scientific statement from the American Heart Association on acute myocardial infarction in women. Sex-specific differences exist in the presentation, pathophysiological mechanisms, and outcomes in patients with acute myocardial infarction. This statement provides a comprehensive review of the current evidence of the clinical presentation, pathophysiology, treatment, and outcomes of women with acute myocardial infarction.

Cardiac Rupture: New Features of the Old Disease

OBJECTIVES

Myocardial rupture is a rare but a fatal complication of acute myocardial infarction. During recent years, treatment strategies of acute myocardial infarction have changed. Primary percutaneous coronary interventions have replaced fibrinolytic therapy, thus reducing one of the major risk factors for myocardial rupture. In this work, we describe a group of patients who suffered myocardial rupture, none of whom were treated with thrombolytic therapy.

METHODS

The digital database of our hospital was searched for all patients who experienced myocardial rupture between 2008 and 2015. The demographic, clinical, angiographic and echocardiographic data of these patients were analyzed.

RESULTS

Out of 2,380 patients admitted with acute myocardial infarction, 12 (0.5%) developed myocardial rupture. The mean age was 78 years, and there were 7 males and 5 females. Ten patients already had pericardial effusion on admission. Seven patients underwent coronary angiography, whilst primary percutaneous intervention was performed in 4 patients. Six patients entered the operating room and all survived the procedure. All patients who were treated conservatively died due to rupture. Factors related to the treatment strategy were advanced age (≥ 90 years) and cognitive impairment.

CONCLUSIONS

The risk of myocardial rupture may be diminished by primary coronary intervention during myocardial infarction, but mortality remains high. An early, comprehensive echocardiographic examination and rapid surgery may contribute to improved survival.

Prompt Recognition of Left Ventricular Free-Wall Rupture Aided by the Use of Contrast Echocardiography

In the modern period of reperfusion, left ventricular free-wall rupture occurs in less than 1% of myocardial infarctions. Typically, acute left ventricular free-wall rupture leads to sudden death from immediate cardiac tamponade. We present the case of a 59-year-old woman who sustained a posterior-wall myocardial infarction and subsequent cardiac arrest with pulseless electrical activity. A bedside transthoracic echocardiogram showed pericardial effusion with cardiac tamponade. Emergency pericardiocentesis yielded 500 mL of blood, and spontaneous circulation returned. Contrast-enhanced echocardiograms revealed inferolateral akinesis and a new, small myocardial slit with systolic extrusion of contrast medium, consistent with left ventricular free-wall rupture. During immediate open-heart surgery, a small hole in an area of necrotic tissue was discovered and repaired. This case highlights the usefulness of bedside contrast-enhanced echocardiography in confirming acute left ventricular free-wall rupture and enabling rapid surgical treatment.

Use of intra-aortic balloon pump support for oozing-type cardiac rupture after acute myocardial infarction

Left ventricular free wall rupture usually leads to acute hemopericardium and sudden cardiac death resulting in cardiac tamponade. Rarely, only a few patients with subacute free wall rupture such as oozing-type ventricular rupture or left ventricular false aneurysm may permit time for pericardiocentesis and surgery. We report a 63-year-old man with ST-elevation myocardial infarction who underwent primary percutaneous coronary intervention about 12 hours from the onset, and cardiac tamponade occurred on the second day. An intra-aortic balloon pump (IABP) was immediately inserted for hemodynamic support. After 100 mL of pericardial fresh blood was drained from the percardial cavity, his hemodynamic collapse was promptly improved with IABP support. In the following 24 hours, about 600 mL of hemorrhagic pericardial fluid was drained. The most likely diagnosis was concerning for oozing-type ventricular rupture, and a conservative approach was decided. The patient survived to the acute phase under IABP support and was discharged with complete recovery.

Trends in the clinical and pathological characteristics of cardiac rupture in patients with acute myocardial infarction over 35 years

Background

There is little known about whether the clinical and pathological characteristics and incidence of cardiac rupture (CR) in patients with acute myocardial infarction (AMI) have changed over the years.

Methods and Results

The incidence and clinical characteristics of CR were investigated in patients with AMI, who were divided into 3 cohorts: 1977–1989, 1990–2000, and 2001–2011. Of a total of 5699 patients, 144 were diagnosed with CR and 45 survived. Over the years, the incidence of CR decreased (1977–1989, 3.3%; 1990–2000, 2.8%; 2001–2011, 1.7%; P=0.002) in association with the widespread adoption of reperfusion therapy. The mortality rate of CR decreased (1977–1989, 90%; 1990–2000, 56%; 2001–2011, 50%; P=0.002) in association with an increase in the rate of emergent surgery. In multivariable analysis, first myocardial infarction, anterior infarct, female sex, hypertension, and age >70 years were significant risk factors for CR, whereas impact of hypertension on CR was weaker from 2001 to 2011. Primary percutaneous coronary intervention (PPCI) was a significant protective factor against CR. In 64 autopsy cases with CR, myocardial hemorrhage occurred more frequently in those who underwent PPCI or fibrinolysis than those who did not receive reperfusion therapy (no reperfusion therapy, 18.0%; fibrinolysis, 71.4%; PPCI, 83.3%; P=0.001).

Conclusions

With the development of medical treatment, the incidence and mortality rate of CR have decreased. However, first myocardial infarction, anterior infarct, female sex, and old age remain important risk factors for CR. Adjunctive cardioprotection against reperfusion‐induced myocardial hemorrhage is emerging in the current PPCI era.

Effect of B-value in revealing postinfarct myocardial microstructural remodeling using MR diffusion tensor imaging

Nonmonoexponential diffusion behavior has been previously reported to exist in some biological tissues, making quantification of diffusion tensor imaging (DTI) indices dependent on diffusion sensitivity of b-value. This study aims to investigate the effect of b-value in revealing postinfarct myocardial microstructural remodeling in ex vivo hearts. DTI scans were performed on heart samples 1, 3, 5, and 7 days after infarction induction as well as intact controls with b-values of 500 to 2500s/mm(2). DTI indices, including fractional anisotropy (FA), and mean and directional diffusivities, were measured in infarct, adjacent and remote regions with zero and each non-zero b-values respectively using conventional DTI analysis. Experimental results showed that these DTI indices decreased gradually with b-values in all regions and groups. Optimal b-values were found to vary with targeted DTI indices, and could strengthen DTI ability in revealing myocardium degradation with using conventional DTI approach. Specifically, FA showed the most sensitive detection of fiber integrity degradation at moderate b-values (≈1500 to 2000s/mm(2)), and the greatest ability of mean and directional diffusivities in monitoring diffusivity alteration occurred at relatively small b-values (≤1500s/mm(2)) during the necrotic and fibrotic phases. These findings may provide useful information for DTI protocol parameter optimization in assessing heart microstructures at other pathological or in vivo states in the future.

Left ventricular pseudoaneurysm complicating inferior myocardial infarction: a case report

Acquired pseudoaneurysm of the left ventricle is a very rare disorder and mostly occurs after large transmural myocardial infarction (MI) with peak creatine phosphokinase-MB levels greater than 150 IU/mL. Patients developing left ventricular (LV) pseudoaneurysm usually present with angina or heart failure symptoms. Although different imaging modalities exist, coronary angiography is the gold standard for diagnosis. Surgery is the treatment of choice for LV pseudoaneurysms detected in the first months after MI. Here we report the case of a 74-year-old woman who presented with a relatively small inferior MI due to right coronary artery occlusion and complicated by LV pseudoaneurysm.

The effect of hydrogel injection on cardiac function and myocardial mechanics in a computational post-infarction model

An emerging therapy to limit adverse heart remodelling following myocardial infarction (MI) is the injection of polymers into the infarcted left ventricle (LV). In the few numerical studies carried out in this field, the definition and distribution of the hydrogel in the infarcted myocardium were simplified. In this computational study, a more realistic biomaterial distribution was simulated after which the effect on cardiac function and mechanics was studied. A validated finite element heart model was used in which an antero-apical infarct was defined. Four infarct models were created representing different temporal phases in the progression of a MI. Hydrogel layers were simulated in the infarcted myocardium in each model. Biomechanical and functional improvement of the LV was found after hydrogel inclusion in the ischaemic models representing the early phases of MI. In contrast, only functional but no mechanical restitution was shown in the scar model due to hydrogel presence.

Cardiac rupture in takotsubo cardiomyopathy: a systematic review

BACKGROUND

Takotsubo cardiomyopathy (TSC) and its complications, such as cardiac rupture (CR), are increasingly being reported in the literature. CR is associated with rapid clinical decline and is uniformly fatal if not surgically repaired. To identify patients who developed CR we performed an analysis of all available indexed cases in the literature and compared them with a control group of patients with TSC without rupture.

HYPOTHESIS

Takotsubo cardiomyopathy patients with cardiac rupture do not differ significantly from those without rupture.

METHODS

MEDLINE (2009) was searched for all TSC case reports with CR. Eleven case reports were identified. Using a random sampling method, we selected 12 case reports of TSC without rupture (control). We included our patient with TSC with rupture as the 12th case of TSC cohort with CR (CR group). Demographic and clinical characteristics were compared between CR group and control.

RESULTS

All patients in the TSC group with rupture were female and were significantly older than controls. TSC group with rupture had significantly higher frequency of ST elevation in lead II and absence of T-wave inversion in lead V5 on hospital admission than controls. Mean ejection fraction, systolic blood pressure, and double product, a measure of oxygen demand, was significantly higher in the rupture group compared to controls. The CR group was associated with less frequent use of β-blocker as compared to controls.

CONCLUSIONS

CR as a complication of TSC could be more common than recognized. Higher double product and ejection fraction suggest higher fluctuation of intracardiac pressure and may cause CR in TSC. Use of β blockers in TSC may provide protection against CR.

The impact of hypertension on patients with acute coronary syndromes

Arterial chronic hypertension (HTN) is a well-known cardiovascular risk factor for development of atherosclerosis. In order to explain the relation between HTN and acute coronary syndromes the following factors should be considered: (1) risk factors are shared by the diseases, such as genetic risk, insulin resistance, sympathetic hyperactivity, and vasoactive substances (i.e., angiotensin II); (2) hypertension is associated with the development of atherosclerosis (which in turn contributes to progression of myocardial infarction). From all the registries and the data available up to now, hypertensive patients with ACS are more likely to be older, female, of nonwhite ethnicity, and having a higher prevalence of comorbidities. Data on the prognostic role of a preexisting hypertensive state in ACS patients are so far contrasting. The aim of the present paper is to focus on hypertensive patients with ACS, in order to better elucidate whether these patients are at higher risk and deserve a tailored approach for management and followup.

Cardiac rupture after myocardial infarction: new insights from murine models

Cardiac rupture after a myocardial infarction is an uncommon event with devastating consequences. Although the clinical features of rupture have been described, the genetic and molecular influences on this outcome in patients are less certain. In mice, at least 17 genetic models have been developed that enhance or suppress the likelihood of rupture postmyocardial infarction. The purpose of this review is to describe these recent advances, recognizing that nearly all of the information has been obtained from mouse models of free wall rupture. Although it is probable that the same genetic determinants apply to septal and papillary muscle rupture, the possibility remains that there are unique modulators of risk for rupture at differing anatomic sites within the heart. It is likely that the candidate genes also influence rupture in humans, although this conclusion must be confirmed. The mouse models will be helpful to direct future proteomic and genomic studies in patients and may already suggest certain fundamental pathways. For example, the essential role of collagen production and stabilization postmyocardial infarction may direct therapies to enhance collagen cross-linking and limit its degradation as a strategy to reduce rates of rupture and enhance myocardial healing.

Contained rupture of left ventricular false aneurysm after acute myocardial infarction secondary to left anterior descending artery embolism

Left ventricular free wall rupture is a rare complication of acute myocardial infarction and accounts for a significant number of fatalities. Pseudoaneurysm is a variety of left ventricular rupture whereby the pericardium seals the defect, forming the wall of the pseudoaneurysm. The diagnosis is usually confirmed with echocardiography, and emergent surgical repair is required in suspected impending rupture. The present report describes the case of a 58-year-old woman who presented with a myocardial infarction due to distal left anterior descending artery occlusion, complicated by ventricular pseudoaneurysm with impending rupture. The patient had an otherwise normal coronary tree.

Complications of myocardial infarction

Echocardiography is a most useful bedside tool to help in the diagnosis and management of critically ill patients after acute myocardial infarction. In most instances, the mechanism of unexplained shock will be elucidated. Transesophageal echocardiography can further delineate the mechanical complications of myocardial infarction when the transthoracic echocardiogram may not be adequate. This article will focus on the mechanical complications of myocardial infarction in patients who most often present with cardiogenic shock or acute pulmonary edema. Each clinical entity is discussed, and illustrative echocardiograms are provided.

Structure and Mechanics of Healing Myocardial Infarcts

Therapies for myocardial infarction have historically been developed by trial and error, rather than from an understanding of the structure and function of the healing infarct. With exciting new bioengineering therapies for myocardial infarction on the horizon, we have reviewed the time course of structural and mechanical changes in the healing infarct in an attempt to identify key structural determinants of mechanics at several stages of healing. Based on temporal correlation, we hypothesize that normal passive material properties dominate the mechanics during acute ischemia, edema during the subsequent necrotic phase, large collagen fiber structure during the fibrotic phase, and cross-linking of collagen during the long-term remodeling phase. We hope these hypotheses will stimulate further research on infarct mechanics, particularly studies that integrate material testing, in vivo mechanics, and quantitative structural analysis.

[Mechanical complications of acute myocardial infarction]

Rupture of the left ventricular myocardium during the course of an acute myocardial infarction may affect the free wall, the interventricular septum, or the papillary muscles. When a rupture occurs, it is referred to as a mechanical complication of acute myocardial infarction. All mechanical complications may lead to cardiogenic shock. However, the location of the rupture can often be suspected clinically. To confirm the diagnosis, echocardiography must be performed. Since the advent of thrombolytic therapy and percutaneous coronary intervention, the incidence of mechanical complications has declined. Even though mortality remains high, their recognition is important since survivors may have an excellent long-term prognosis. The cases convey two main messages: 1) Mechanical complications must be carefully searched for in any patient with an acute coronary syndrome and signs of cardiogenic shock and/or a systolic murmur. 2) Aggressive and timely medical and surgical treatment should be provided even though in a substantial proportion of these patients prognosis may be dismal.