Mechanical and electrical complications of acute myocardial infarction

Mechanical complications in STEMI: prevalence and mortality trends in the primary PCI era. The Ruti-STEMI registry

INTRODUCTION AND OBJECTIVES

Mechanical complications confer a dreadful prognosis in ST-elevation myocardial infarction (STEMI). Their prevalence and prognosis are not well-defined in the current era of primary percutaneous coronary intervention (pPCI) reperfusion networks. We aimed to analyze prevalence and mortality trends of post-STEMI mechanical complications over 2 decades, before and after the establishment of pPCI networks.

METHODS

Prospective, consecutive registry of STEMI patients within a region of 850 000 inhabitants over 2 decades: a pre-pPCI period (1990-2000) and a pPCI period (2007-2017). We analyzed the prevalence of mechanical complications, including ventricular septal rupture, papillary muscle rupture, and free wall rupture (FWR). Twenty eight-day and 1-year mortality trends were compared between the 2 studied decades.

RESULTS

A total of 6033 STEMI patients were included (pre-pPCI period, n=2250; pPCI period, n=3783). Reperfusion was supported by thrombolysis in the pre-pPCI period (99.1%) and by pPCI in in the pPCI period (95.7%). Mechanical complications developed in 135 patients (2.2%): ventricular septal rupture in 38 patients, papillary muscle rupture in 24, and FWR in 73 patients. FWR showed a relative reduction of 60% in the pPCI period (0.8% vs 2.0%, P<.001), without significant interperiod changes in the other mechanical complications. After multivariate adjustment, FWR remained higher in the pre-pPCI period (OR, 1.93; 95%CI, 1.10-3.41; P=.023). At 28 days and 1 year, mortality showed no significant changes in all the mechanical complications studied.

CONCLUSIONS

The establishment of regional pPCI networks has modified the landscape of mechanical complications in STEMI. FWR is less frequent in the pPCI era, likely due to reduced transmural infarcts.

Acute partial papillary muscle rupture as a rare complication following non-ST elevation myocardial infarction

Papillary muscle rupture is a life-threatening complication of acute myocardial infarction that most commonly occurs 2-7 days after the infarct. We present a rare case of acute partial anterolateral papillary muscle rupture following non-ST elevation myocardial infarction. Our patient was an elderly male who had a detached anterolateral papillary muscle, which required emergent mitral valve replacement. Papillary muscle rupture is a rare complication of acute myocardial infarction, and anterolateral muscle rupture occurs even less commonly. When papillary muscle rupture is diagnosed, patients need to be emergently referred to cardiothoracic surgery as mortality without surgery is over 90% within a week.

A comprehensive and easy-to-use ECG algorithm to predict the coronary occlusion site in ST-segment elevation myocardial infarction

BACKGROUND

Several electrocardiogram (ECG) criteria have been proposed to predict the location of the culprit occlusion in specific subsets of patients presenting with ST-segment elevation myocardial infarction (STEMI). The aim of this study was to develop, through an independent validation of currently available criteria, a comprehensive and easy-to-use ECG algorithm, and to test its diagnostic performance in real-world clinical practice.

METHODS

We analyzed ECG and angiographic data from 419 consecutive STEMI patients submitted to primary percutaneous coronary intervention over a one-year period, dividing the overall population into derivation (314 patients) and validation (105 patients) cohorts. In the derivation cohort, we tested >60 previously published ECG criteria, using the decision-tree analysis to develop the algorithm that would best predict the infarct-related artery (IRA) and its occlusion level. We further assessed the new algorithm diagnostic performance in the validation cohort.

RESULTS

In the derivation cohort, the algorithm correctly predicted the IRA in 88% of cases and both the IRA and its occlusion level (proximal vs mid-distal) in 71% of cases. When applied to the validation cohort, the algorithm resulted in 88% and 67% diagnostic accuracies, respectively. In a real-world comparative test, the algorithm performed significantly better than expert physicians in identifying the site of the culprit occlusion (P = .026 vs best cardiologist and P < .001 vs best emergency medicine doctor).

CONCLUSIONS

Derived from an extensive literature review, this comprehensive and easy-to-use ECG algorithm can accurately predict the IRA and its occlusion level in all-comers STEMI patients.

Rupture of Papillary Muscle and Chordae Tendinae Complicating STEMI: A Call for Action

Papillary muscle rupture (PMR) or chordae tendinae rupture (CTR) is a rare but lethal complication after ST elevation myocardial infarction (STEMI). Due to the rarity of this condition, there are limited studies defining its epidemiology and outcomes. This is a retrospective study from Nationwide Inpatient Sample database from 2002 to 2014 of patients with STEMI and PMR/CTR. Outcomes of interest were incidence of in-hospital mortality, cardiogenic shock (CS), utilization of mechanical circulatory support (MCS) devices and mitral valve procedures (MVPs) among patients with and without rupture. We also performed simulation using the cardiovascular model to better understand the hemodynamics of severe mitral regurgitation and effects of different medications and device therapy. We identified 1,888 patients with STEMI complicated with PMR/CTR. Most of the patients were >65 years of age (65.3%), male (63.6%), and white (82.3%). They had significantly higher incidence of CS, cardiac arrest, and utilization of MCS devices. In-hospital mortality was higher in patients with rupture (41% vs. 7.40%, p < 0.001) which remained unchanged over the study period. Hospitalization cost and length of stay was also higher in them. MVP and revascularization led to better survival rates (27.9% vs. 60.6%, adjusted OR: 0.14; 95% CI: 0.10-0.19; p < 0.001). Despite significant advancement in the revascularization strategy, PMR/CTR after STEMI continues to portend poor prognosis with high inpatient mortality. Cardiogenic shock is a common presentation and is associated with significantly inpatient mortality. Future studies are needed determine the best strategies to improve outcomes in patients with STEMI with PMR/CTR and CS.

Percutaneous mitral valve repair with MitraClip XTR for acute mitral regurgitation due to papillary muscle rupture

Papillary muscle rupture is an infrequent and highly morbid mechanical complication of acute myocardial infarction. Surgical repair or replacement is traditionally considered first-line therapy. However, many of these patients present in extremis with prohibitively high surgical risk. Repair of mitral regurgitation with the MitraClip device (Abbot Vascular, Menlo Park, CA, USA) is an established therapy to treat degenerative and functional mitral regurgitation. We present a case of successful repair of severe mitral regurgitation due to papillary muscle rupture in the setting of acute myocardial infarction. A two-clip strategy resulted in mild residual mitral regurgitation with resolution of cardiogenic shock and refractory hypoxemia requiring veno-venous extracorporeal membrane oxygenation. Six-month follow-up echocardiogram identified durable results with mild mitral regurgitation and left ventricular ejection fraction of 63 %. Our case demonstrates that percutaneous mitral valve repair with MitraClip is a well-tolerated procedure that can provide acute and long-term benefit for patients with acute mitral regurgitation due to papillary muscle rupture who are at prohibitively high surgical risk. .

Acute Myocardial Infarction and Papillary Muscle Rupture in the COVID-19 Era

Mechanical complications of acute myocardial infarction are infrequent in the modern era of primary percutaneous coronary intervention, but they are associated with high mortality rates. Papillary muscle rupture with acute severe mitral regurgitation is one such life-threatening complication that requires early detection and urgent surgical intervention. (Level of Difficulty: Beginner.).

The Use of Beta Blockers in Takotsubo Syndrome as Compared to Acute Coronary Syndrome

BACKGROUND

Takotsubo syndrome (TTS) and acute coronary syndrome (ACS) patients have a similar mortality rate. In this study, we sought to determine the short- and long-term outcome of TTS patients as compared to ACS patients both treated with beta-blockers.

OBJECTIVES

In the present study we described the data of 5 years of follow up of 103 TTS and 422 ACS patients both treated with beta-blockers.

METHODS

Data from TTS patients were included retrospectively and prospectively, ACS patients were included retrospectively. All retrospectively included patients have been followed up for 5 years. The end point in this study was the occurrence of death.

RESULTS

TTS affected significantly more women (87.4%) than ACS (34.6%) (p < 0.01). TTS patients suffered significantly more often from thromboembolic events (14.6% versus 2.1%; p < 0.01) and cardiogenic shock (11.9% versus 3.6%; p < 0.01) than the ACS group. TTS patients had a significantly higher long-term mortality (within 5 years) as compared to ACS patients (17.5% versus 3.6%) (p < 0.01). Patients of the TTS group compared to the ACS group did not benefit from combination of beta-blockers and ACE-inhibitors in terms of long-term mortality (p < 0.01). As we compare TTS patients who were treated with beta-blockers and ACE-inhibitors versus single use of beta-blockers there was no difference in long-term mortality (p = 0.918).

CONCLUSION

TTS patients had a significantly higher long-term mortality (within 5 years) than patients with an ACS.

Rupture of mitral valve papillary muscle: a rare complication following myocardial infarction

Here we present a rare clinical presentation of papillary muscle rupture in a 55-year-old man who presented to accident and emergency department with chest pain and was diagnosed as having had a non-ST elevation myocardial infarction. During the admission, he developed papillary muscle rupture due to the myocardial infarction resulting in acute mitral regurgitation. This caused significant haemodynamic compromise needing emergency admission to the intensive care unit and eventually surgery to replace the valve.

Dysrhythmias and heart failure complicating acute myocardial infarction: An emergency medicine review

INTRODUCTION

Patients with acute myocardial infarction (AMI) may suffer several complications after the acute event, including dysrhythmias and heart failure (HF). These complications place patients at risk for morbidity and mortality.

OBJECTIVE

This narrative review evaluates literature and guideline recommendations relevant to the acute emergency department (ED) management of AMI complicated by dysrhythmia or HF, with a focus on evidence-based considerations for ED interventions.

DISCUSSION

Limited evidence exists for ED management of dysrhythmias in AMI due to relatively low prevalence and frequent exclusion of patients with active cardiac ischemia from clinical studies. Management decisions for bradycardia in the setting of AMI are determined by location of infarction, timing of the dysrhythmia, rhythm assessment, and hemodynamic status of the patient. Atrial fibrillation is common in the setting of AMI, and caution is warranted in acute rate control for rapid ventricular rate given the possibility of compensation for decreased ventricular function. Regular wide complex tachycardia in the setting of AMI should be managed as ventricular tachycardia with electrocardioversion in the majority of cases. Management directed towards HF from left ventricular dysfunction in AMI consists of noninvasive positive pressure ventilation, nitroglycerin therapy, and early cardiac catheterization. Norepinephrine is the first line vasopressor for patients with cardiogenic shock and hypoperfusion on clinical examination. Early involvement of a multi-disciplinary team is recommended when caring for patients in cardiogenic shock.

CONCLUSIONS

This review discusses considerations of ED management of dysrhythmias and HF associated with AMI.

Modern Management of ST-Segment Elevation Myocardial Infarction

Disruption of intracoronary plaque with thrombus formation resulting in severe or total occlusion of the culprit coronary artery provides the pathophysiologic foundation for ST-segment elevation myocardial infarction (STEMI). Management of STEMI focuses on timely restoration of coronary blood flow along with antithrombotic therapies and secondary prevention strategies. The purpose of this review is to discuss the epidemiology, pathophysiology, and diagnosis of STEMI. In addition, the review will focus on guideline-directed therapy for these patients and review potential associated complications.

Cell Competition During Growth and Regeneration

Tissue growth and regeneration are autonomous, stem-cell-mediated processes in which stem cells within the organ self-renew and differentiate to create new cells, leading to new tissue. The processes of growth and regeneration require communication and interplay between neighboring cells. In particular, cell competition, which is a process in which viable cells are actively eliminated by more competitive cells, has been increasingly implicated to play an important role. Here, we discuss the existing literature regarding the current landscape of cell competition, including classical pathways and models, fitness fingerprint mechanisms, and immune system mechanisms of cell competition. We further discuss the clinical relevance of cell competition in the physiological processes of tissue growth and regeneration, highlighting studies in clinically important disease models, including oncological, neurological, and cardiovascular diseases.

Case report: necrosis of the anterolateral papillary muscle--an unusual mechanical complication of myocardial infarction

We report the case of a 66-year-old woman with no significant past medical history who presented to the Emergency Department at Houston Methodist Hospital with 24 hours of chest pain. An electrocardiogram was done, an electrocardiogram confirmed a posterolateral ST elevation myocardial infarction. An immediate and successful percutaneous coronary intervention of a totally occluded ramus intermedius was performed. Six hours later she developed pulmonary edema, cardiogenic shock, severe acidosis, and anuria. Echocardiography showed severe mitral regurgitation due to a ruptured anterolateral papillary muscle, and emergency surgery revealed necrosis of this muscle. A bioprosthetic mitral valve was placed, and extracorporeal membrane oxygenation was needed for 3 days. This is a rare mechanical complication of myocardial infarction, which usually affects the posteromedial papillary muscle. The patient subsequently made a good recovery. One month later, just prior to discharge home, the patient developed pneumonia and sepsis, and she expired from multiorgan failure.

Surgical versus medical management of patients with acute ischemic mitral regurgitation: a systematic review

Aims

Acute ischemic mitral regurgitation (MR) is seen in patients with myocardial infarction and is associated with increased morbidity and mortality. The optimal treatment strategy of this condition however, is not well established. The aim of this manuscript is to conduct a systematic review of the medical literature to assess the relative benefits and harms of mitral valve surgery with medical therapy versus medical management alone for patients with acute ischemic MR of at least moderate severity.

Methods

We performed a literature search in MEDLINE, Embase.com, and Cochrane Central Register of Controlled Trials. We restricted the search to randomized clinical trials comparing surgical to medical management of acute ischemic MR. Exclusion criteria included non-randomized trials, trials enrolling patients with non-ischemic MR, and trials excluding acute ischemic MR. The primary outcomes were short-term and long term mortality. Two reviewers (WA, WA) screened titles and abstracts of identified citations independently and in duplicate using calibration exercises and standardized screening forms.

Results

The search strategy identified 887 citations (137 were duplicates and removed). Of the 750 titles, 709 were excluded (519 were non-relevant and 190 were review articles and case reports). Of the 41 remaining abstracts, 37 were retrospective cohorts and four excluded acute MR, leaving no eligible study for analysis. An ongoing study that is being conducted at Southern Illinois University entitled by “Medical Versus Surgical Management of Patients With Moderate Mitral Regurgitation Following Percutaneous Coronary Intervention for Myocardial Infarction: A Pilot Prospective Randomized Trial” was identified; however, it was just withdrawn after failing to enroll patients during 4 years.

Conclusion

This is an empty systematic review that identified no published randomized trials for the management of acute MR complicating acute MI. The only ongoing randomized study that was identified was just withdrawn after failing to enroll patients. There is an urgent need for conducing proper randomized trials in order to guide informed decision making in the treatment of acute ischemic MR.

PROSPERO registration number CRD42013005843

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-015-1704-9) contains supplementary material, which is available to authorized users.

A forgotten devil; Rupture of mitral valve papillary muscle

Background:

Papillary muscle rupture is one of the catastrophic mechanical complications following myocardial infarction. Rupture leads to acute mitral valve regurgitation, pulmonary edema, and cardiogenic shock. Survival is dependent on prompt recognition and surgical intervention.

Cases Report:

We present two cases where acute myocardial infarction was complicated by papillary muscle rupture resulting in severe mitral regurgitation and cardiogenic shock. In both cases rupture occurred within one week of infarction. Both patients did not receive coronary revascularization; one patient presented late after the onset of chest pain, the other patient percutaneous revascularization attempted and was not successful. Both patients suffered an inferior wall infarction. Echocardiogram demonstrated severe mitral regurgitation with a jet directed posteriorly. In both cases rupture of the posteromedial papillary muscle resulted in flail of the anterior mitral valve leaflet, thus serving as a reminder that both the anterior and the posterior leaflets attach to both papillary muscles.

Conclusions:

While one case had a good outcome, the other reinforces the fact that this is a very serious complication requiring prompt recognition and treatment.

Modern management of acute myocardial infarction

Disruption of intracoronary plaque with thrombus formation provides the pathophysiologic foundation for acute coronary syndromes, which comprise ST-segment myocardial infarction, non-ST-segment myocardial infarction, and unstable angina. Management differs depending on whether ST-segment elevation is present, but the general principles of timely restoration of coronary blood flow and initiation of secondary prevention strategies are applicable to all patients. The purpose of this review is to discuss first the epidemiology, pathophysiology, and diagnosis of acute myocardial infarction. Risk stratification and therapy for patients with ST-segment elevation myocardial infarction and non-ST-segment elevation acute coronary syndromes are then reviewed along with diagnosis and management of the complications of myocardial infarction.

Post myocardial infarction cardiogenic shock: a review of current therapies

Cardiogenic shock is often a devastating consequence of acute myocardial infarction (MI) and portends to significant mortality and morbidity. Despite improvements in expediting the time to treatment and enhancements in available medical therapy and reperfusion techniques, cardiogenic shock remains the most common cause of mortality following MI. Post-MI cardiogenic shock most commonly occurs as a consequence of severe left ventricular dysfunction. Right ventricular (RV) MI must also be considered. Mechanical complications including acute mitral regurgitation, ventricular septal rupture, and ventricular free-wall rupture can also lead to cardiogenic shock. Rapid diagnosis of cardiogenic shock and its underlying cause is pivotal to delivering definitive therapy. Intravenous vasoactive agents and mechanical support devices may temporize the patient's hemodynamic status until definitive therapy by percutaneous or surgical intervention can be performed. Despite prompt management, post-MI cardiogenic shock mortality remains high.

Echocardiographic evaluation of systolic heart failure

Echocardiography is the most commonly used modality for evaluating left ventricular size and function in the context of systolic heart failure. Traditional techniques, though extensively used, have their limitations and more recently several newer technologies have emerged that are more reproducible, provide prognostic information, guide therapies and have an important role in monitoring progress. This review will evaluate the traditional and more novel techniques used and briefly provide an overview of the role of echocardiography in guiding and monitoring therapies in patients with systolic heart failure.

Imaging studies in patients with heart failure: current and evolving technologies

Technological advances continue to expand the clinical role of echocardiography in the intensive care unit, particularly in patients with heart failure. It has many advantages over tomographic techniques such as echo cardiac magnetic resonance imaging and cardiac computed tomography, can provide rapid bedside cardiac assessment, and facilitate emergent decision-making for critically ill patients. Image quality problems in the intensive care setting have largely been overcome by the use of harmonic imaging, contrast opacification, and when indicated, transesophageal echocardiography. Newer techniques promise to advance the scope and prognostic power of echocardiography, and to expand the portability and availability of this tool.

Heart failure in the twenty-first century: is it a coronary artery disease or hypertension problem?

Hypertension and coronary disease are major risk factors for the incidence and progression of heart failure. These two risk factors frequently coexist, and have additive and synergistic effects that promote both left ventricular remodeling and heart failure in the general population. The relative contributions of these two risk factors to heart failure burden in the community may vary based on age, gender, and race. In general, attribution of heart failure in the community to solely one of these two risk factors is inappropriate. Prevention of both hypertension and coronary disease is important for preventing heart failure in the twenty-first century.

Ventricular free wall rupture in acute myocardial infarction

Despite a progressive reduction in acute myocardial infarction mortality over the years, death related to ventricular free wall rupture has not changed. This is mostly related to the catastrophic presentation and death within minutes in the majority of these patients. Once rupture is suspected, bedside echocardiography should be performed immediately, followed by pericardiocentesis and repair of the rupture site as quickly as possible. Measures to prevent cardiac rupture include the administration of beta-blockers and angiotensin-converting enzyme inhibitors unless contraindications exist, and the avoidance of steroidal and nonsteroidal anti-inflammatory agents such as ibuprofen and indomethacin.

Catheter-based fixation of the mitral valve after acute papillary muscle rupture: a new technique for temporary hemodynamic stabilization

We describe a new, catheter-based method for temporary management of hemodynamic instability after papillary muscle rupture in a patient with an acute myocardial infarction.

Subacute cardiac rupture complicating myocardial infarction. A case report

The authors have focused this study on the emergence of subacute ventricular free wall rupture in a seventy-six-year-old patient admitted to hospital for inferior acute myocardial infarction. After six days he showed clinical signs of bradycardia and hypotension evolving to electromechanical dissociation. Given an adequate pharmacologic therapy, the patient was submitted to echocardiography, which was believed to be consistent with myocardial rupture, showing a moderate to large pericardial effusion. Pericardiocentesis of 150 mL of bloody fluid resulted in a further improvement in his hemodynamics. The patient underwent cardiac surgery with repair of the myocardial rupture through a large diaphragmatic infarction by a Dacron polyester fiber graft and pacemaker placement. In conclusion the authors confirm the relevant role of clinical data such as persistent chest pain and hemodynamic instability and the value of echocardiography in identifying subacute myocardial free wall rupture after an episode of acute myocardial infarction.

Successful repair of combined septal and biventricular free wall rupture after acute myocardial infarction

The following case is the first report of successful repair of combined left and right ventricular free wall and ventricular septal rupture. Reports of left ventricular free wall and septal rupture and reports of right ventricular free wall and septal rupture have been published both with and without successful surgical repair. This case demonstrates the presence of left and right ventricular free wall rupture along with septal rupture based upon cardiac catheterization and operative findings. In spite of her severe mechanical complications and prolonged hospital course, the patient is completely functional 1 year after surgical repair.

The potential impact of the thrombolytic era on cardiac rupture complicating acute myocardial infarction

Cardiac rupture complicating acute myocardial infarction (AMI) remains a serious diagnostic and therapeutic challenge. The authors present 27 consecutive patients who died from cardiac rupture following AMI. These included 22 patients from 1975 through 1983 (prethrombolytic era) and 5 patients from 1984 through 1992 (postthrombolytic era) and all had postmortem examination. There were 16 men and 11 women with a mean age of seventy-two years. Myocardial infarction was anterior/anterolateral in 10 and inferior/inferoposterior in 17. Cardiac rupture followed AMI within one day in 14 (52%), two to five days in 8 (30%), and six to fourteen days in 5 (18%). Chest pain followed by sudden hypotension leading to electromechanical dissociation was the common terminal event. Cardiopulmonary resuscitation was unsuccessful in all patients. Postmortem findings showed three-vessel coronary disease in 21 (78%) and two-vessel disease in 6 (22%). Isolated free left ventricular wall rupture was found in 22 (81%), was anterior/anterolateral in 13 (48%), posterior in 9 (33%), and in conjunction with interventricular septum or papillary muscle in 5 (18%). Patients encountered in this series were mostly elderly hypertensives with multivessel coronary disease and postinfarction angina. Furthermore, cardiac rupture commonly occurred within the first five days of AMI and cardiopulmonary resuscitation was uniformly unsuccessful. During the thrombolytic era at their institution, this complication is now being seen much less often. These observations suggest that such interventions are expected to have a favorable impact on reducing the incidence of this catastrophic event.

Emergency department two-dimensional echocardiography in the diagnosis of nontraumatic cardiac rupture

Myocardial rupture is a catastrophic complication of acute myocardial infarction that usually results in sudden death. If diagnosed quickly, patients with myocardial rupture may be salvaged. This report describes the application of emergency department two-dimensional echocardiography in the diagnosis of six cases of myocardial rupture over two years. Each demonstrated a characteristic hemopericardium on limited single-window examination. These included four patients who met institutional guidelines for thrombolytic therapy. Three patients survived surgical repair, with two long-term survivors.