Case report: ST-elevation myocardial infarction complications. How far will you go?

ABSTRACT

Herein, we review the critical role of a multi-disciplinary team approach in managing the intricate complications of ST-elevation myocardial infarction (STEMI) complicated by cardiogenic shock (CS). Mechanical circulatory support (MCS) implantation represents a potentially life-saving intervention, often serving as a bridge to heart transplantation (HTx). However, complications from prior interventions, in patients receiving MCS due to STEMI-CS, may present additional challenges to successful HTx candidacy. A 63-year-old male suffered out-of-hospital cardiac arrest and was hospitalized due to acute anterior STEMI-CS. Emergency percutaneous coronary intervention was performed in the setting of cardiopulmonary resuscitation. Despite successful revascularization and subsequent optimal medical therapy hemodynamic status remained compromised, the decision was made to implant a HeartMate 3 (HM3) left ventricular assist device (LVAD) as a bridge to HTx. HM3 LVAD was implanted without complications and patient was weaned from mechanical ventilation. The later postoperative period was complicated by infections leading to the LVAD-related complications. Moreover, the patient experienced repeated episodes of stridor, which were attributed to significant tracheal stenosis (due to temporary tracheostomy). Finally, a suitable heart donor was found and a successful HTx was performed.

1. Introduction

Cardiogenic shock (CS) still remains a catastrophic consequence of ST-elevation myocardial infarction (STEMI) and the mortality of patients with CS is high, ranging from 27% to 51% even though the use of more aggressive and invasive strategies has raised over the last decade [1–3]. We present the case of 63-year-old man who was admitted to our institution after successful community cardiopulmonic resuscitation (CPR) due to acute anterior STEMI and CS. Herein, we review the critical role of a multi-disciplinary team approach in managing the intricate complications of STEMI and CS. Written informed consent was obtained from the patient for the publication of this case and photos associated with this case report.

2. Case report

A 63-year-old male with a medical history of arterial hypertension and type 2 diabetes mellitus (managed with metformin) experienced an out-of-hospital cardiac arrest. CPR was successfully administered on-site, and the patient was subsequently transferred to a tertiary care center. Initial electrocardiography (ECG) demonstrated an anterior STEMI with prolonged asystolic pauses. Emergency coronary angiography performed during ongoing CPR revealed critical stenosis of the left main coronary artery (LMCA) and 90% stenosis of the proximal left anterior descending artery (LAD). Primary percutaneous coronary intervention (PCI) was performed, achieving TIMI 3 perfusion flow following the deployment of drug-eluting stents (Figure 1). Despite successful revascularization and mechanical ventilation, hypoxemia and hemodynamic instability progressed, necessitating the initiation of short-term mechanical circulatory support (MCS). Peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) was initiated (under CPR) via a percutaneous femoral approach under fluoroscopic guidance. Transesophageal echocardiography (TEE) revealed severe left ventricular (LV) systolic dysfunction with LV ejection (LVEF) fraction of 10–15%. After one week of VA-ECMO, the patient’s hemodynamic functions stabilized, enabling successful weaning from ECMO and extubation. However, the patient experienced progressive deterioration in both respiratory and cardiac function one week after extubation, requiring re-intubation and high-dose inotropic support. Repeated TEE revealed severe LV systolic dysfunction with moderate-to-severe secondary mitral and tricuspid regurgitation. TEE also demonstrated moderate pulmonary hypertension with mild right ventricle dilatation and preserved function. Given the absence of significant recovery in LV systolic function 35 days post-STEMI and high-dose inotropic support, the multidisciplinary heart team decided implantation of a left ventricular assist device (LVAD). The HeartMate 3 (HM3) LVAD was implanted uneventfully as a bridge to recovery or heart transplantation (HTx). One week post-implantation, a temporary tracheostomy was performed for prolonged airway management. The tracheostomy was removed three weeks later as respiratory function improved. One month post-HM3 LVAD implantation, the patient developed clinical signs of a superficial driveline infection. Over the following six months, he experienced recurrent bloodstream infections caused by Serratia marcescens. Despite extended intravenous antibiotic therapy, FDG-PET/CT scan imaging revealed persistent deep infection at the HM3 LVAD inflow cannula (Figure 2). Indicating a deep device-related persistent infection, the patient’s priority status on the HTx waiting list was elevated. Ten months post-HM3 LVAD implantation, the patient developed recurrent episodes of stridor, secondary to significant tracheal stenosis (CT imaging and bronchoscopic evaluation) following tracheostomy removal (Figure 3). The heart team recommended surgical approach to address the tracheal stenosis, which was successfully performed. Fifteen months after the implantation of the HM3 LVAD, a suitable donor heart became available, and the patient underwent successful HTx. At more than one-year post-transplantation, the patient remains in stable clinical condition.

Figure 1.

(a) Coronary angiography showing critically stenotic left main coronary artery (LMCA) and proximal left anterior descendent (LAD) stenosis of 90%. (b) Coronary angiography after successful LMCA and LAD angioplasty and stenting.

Figure 2.

18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography of the chest revealed moderate, circular FDG uptake around the arterial cannula of the HeartMate3, indicative of reactive or infectious alterations in the tissues surrounding the arterial cannula.

Figure 3.

Computed tomography of the neck and upper chest showing tracheal stenosis.

3. Discussion

Cardiogenic shock related to acute coronary syndrome accounts for approximately 60–80% of all CS cases [4]. Of these, approximately 70% of patients present with STEMI. The incidence of CS is lower in cases of inferior wall MI (9.5%) versus anterior wall MI (14.1%) [1]. MCS devices are reported to be used in 61.0% of cases of anterior MI-associated CS [1].

This case describes a 63-year-old male who presented with an acute anterior STEMI complicated by CS, representing both the initial clinical manifestation and the sequelae of complications associated with underlying coronary artery disease. The etiology of CS in this patient was attributed to a critical stenosis of the left main coronary artery (LMCA) and a subocclusion of the proximal left anterior descending artery (LAD). According to acute total occlusion of the left main coronary artery (ATOLMA) registry data the incidence of STEMI caused by LMCA range from 0.8 to 2.5% in patients undergoing cardiac catheterization [5].

Early successful revascularization and reperfusion is the primary treatment for acute MI [6]. However, in this case, despite successful percutaneous coronary intervention (angioplasty and stenting of the LMCA and LAD, TIMI 3), the patient exhibited persistent hemodynamic instability, necessitating the initiation of MCS (VA-ECMO). Early unloading of the infarcted myocardium and hemodynamic support with MCS devices such as VA ECMO, has demonstrated improved clinical outcomes in patients with acute MI, according to observational studies [7]. Although “LMCA shock syndrome” initially described by Quigley et al. in 1993 was associated with an extremely poor prognosis, regardless of management, with a mortality rate of 94% in STEMI patients with CS and severe LMCA stenosis [5], our clinical case demonstrates a successful outcome in which the patient survived.

Despite advances in coronary revascularization and widespread use of primary percutaneous interventions, cardiogenic shock complicating an acute ST-elevation myocardial infarction remains a clinical challenge with high mortality. The percutaneous assist systems most commonly used in cardiogenic shock due to acute MI are the intra-aortic balloon pump (IABP), venoarterial ECMO, the Impella pump, and the TandemHeart. The large randomized IABP-Shock II Trial did not show a significant reduction in 30-day mortality in cardiogenic shock patients with IABP insertion. The V-A ECMO and Impella devices may be used as a short-term organ support in cardiogenic shock with a potentially reversible underlying cause or in patients who are potential transplant or durable ventricular assist device candidates. In case of refractory cardiac arrest and in cases with combined hypoperfusion and respiratory insufficiency V-A ECMO is often favored. In acute myocardial infarction, CS with predominant left ventricular failure Impella may be preferred based on unloading effect of this device. While the final decision of initiation of short term mechanical circulatory support should be made ideally by a dedicated ‘Shock Team,’ based not solely on thresholds of hemodynamic variables but also on clinical presentation, evaluation of comorbidities, frailty, and patient wishes [8].

It is also crucial to emphasize that in patients with refractory CS who are potential candidates for LVAD implantation, the stabilization of end-organ function and correction of metabolic derangements through the use of ECMO prior to durable LVAD implantation can significantly improve post-LVAD survival [9,10].

Temporary MCS offers the potential for LV and/or RV functional recovery and provides critical time for a more comprehensive evaluation of candidacy for long term LVAD implantation or HTx [10]. A small minority of patients (1.6%) with acute MI-related CS who require LVAD support demonstrated sufficient myocardial recovery (bridge to recovery) to allow for LVAD explantation. Notably, nearly all of these explantations occurred within the first year following LVAD implantation [6]. LVAD associated infection pose increased substantial morbidity and mortality risk. Diagnosing deep-seated LVAD infections remains challenging due to the limitations of conventional imaging techniques. The use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has emerged as a pivotal and guiding diagnostic tool in the early and precise detection of LVAD-related infections. In cases of refractory LVAD-related infection, surgical interventions like device replacement or HTx may be necessary to control the infection. Literature indicates that the majority of heart transplants (HTx) following LVAD implantation occur within a timeframe of 3–15 months post-implantation. This aligns with findings from other studies where early HTx following LVAD implantation is frequently necessitated by complications related to the device (infection, thrombosis and etc.). In our case, heart transplantation (HTx) was postponed and performed later, at 15 months after LVAD implantation, primarily due to significant tracheal stenosis that developed following a previous tracheostomy. Almost 30% of patients with tracheal stenosis were intubated due to CS [11]. Tracheal stenosis is commonly observed among prolonged ventilated patients with tracheostomies, characterized by localized hypergranulation and airway obstruction [12]. Tracheal stenosis is a recognized complication of long-term tracheostomy, which can delay surgical interventions, including HTx, due to the need surgical or interventional management of the airway obstruction.

Due to the scarce of large-scale randomized controlled trials, there is limited data on the optimal management approach for CS complicating MI [13]. Current guidelines recommend using inotropic agents, vasopressors, and MCS to enhance hemodynamics in patients with MI-related CS [14]. However, there is limited evidence demonstrating that these therapies significantly improve mortality rates among these patients [13]. Consequently, mortality remains high, with hospital death rates ranging from 30% to 50%, and there has been minimal improvement over time [14,15]. A multidisciplinary approach involving specialized shock teams is crucial for comprehensive and timely management to optimize patient outcomes [16,17].

4. Conclusions

The management of complications arising from acute myocardial infarction especially in the context of cardiogenic shock, necessitates a comprehensive and multidisciplinary approach. This involves collaboration among cardiologists, cardiac surgeons, intensivists, and other specialists to address the patient’s specific clinical circumstances (mechanical circulatory support, heart transplantation and non-cardiac related complications).

Funding Statement

This paper was not funded.

Author contributions

• Rumbinaite E, Karciauskas D, Vajauskas D, Mamedov A, Jakuskaite G, Zukaite G were responsible for data collection, drafting, and editing of the manuscript.

• Rumbinaite E, Karciauskas D, Jakuska P, Vajauskas D, Mamedov A, Jakuskaite G, Bolys R, Zukaite G, Jankauskiene L, Benetis R, Zaliunas R were responsible for literature review and editing.

• Rumbinaite E was responsible for supervision of the manuscript.

• All authors read and approved the final version of the manuscript.

Disclosure statement

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. No writing assistance was utilized in the production of this manuscript.

Article highlights

• Early unloading of the infarcted myocardium and hemodynamic support with mechanical circulatory support devices, has demonstrated improved clinical outcomes in patients with acute MI.

• Left ventricular assist device (LVAD) associated infection pose increased substantial morbidity and mortality risk. The use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has emerged as a pivotal and guiding diagnostic tool in the early and precise detection of LVAD-related infections.

• Tracheal stenosis is a recognized complication of long-term tracheostomy, which can delay surgical interventions, including HTx, due to the need surgical or interventional management of the airway obstruction.

• A multidisciplinary approach involving specialized shock teams is crucial for comprehensive and timely management to optimize patient outcomes.

Ethical declaration

The authors state that they have obtained verbal and written informed consent from the patient for the inclusion of their medical and treatment history within this case report.