Department of Cardiology, Zealand University Hospital (Roskilde), Roskilde, Denmark
Received Date: 10/09/2020; Published Date: 24/09/2020
*Corresponding author: Line Lisbeth Olesen, MD, Department of Cardiology, Zealand University Hospital (Roskilde), Sygehusvej 10, Roskilde 4000, Denmark. Tel: +45-40830421; E-mail: llole@regionsjaelland.dk; olesen.line@gmail.com
Due to this unfortunate case about irreversible cardiogenic shock after explantation of a CRT, in a patient with unexplained severe infection and with high-risk ischemic cardiomyopathy, it is recommended to disable the LV-function and observe the patient and the EF before deciding to explant a CRT.
Keywords: CRT Explantation; Cardiogenic Shock; LV-Pacing Disabling; Device Infection; Case Report
Abbreviations: ACS= Acute Coronary Syndrome; CRT= Cardiac Resynchronization Therapy; LV= Left Ventricle; EF= Ejection Fraction; COPD= Chronic Obstructive Pulmonary Disease; LM= Left Main Artery; LAD= Left Anterior Descendent Artery; CX= Circumflexus Artery; PCI= Percutaneous Coronary Intervention; CAGB= Coronary Artery Bypass Grafting
Cardiogenic shock in patients with chronic systolic heart failure may result from progressive decline in the ejection fraction or acute deterioration precipitated by cardiac or non-cardiac causes such as acute coronary syndrome (ACS), arrhythmias, sepsis [1-3]. This is the first case to be presented where cardiogenic shock developed within a few hours following removal of a cardiac resynchronization therapy device (CRT). Device infection as well as left ventricular (LV) pacing lead extraction are expected to increase [4-12]. In order to avoid an unfortunate outcome as in the present case it is essential to attempt to identify predictors of difficulties and complications. Prior to proceeding with withdrawal of biventricular pacing and lead extraction the consequences should be evaluated [6,7,10].
This 70-year-old male had been a heavy smoker since his youth and suffered from chronic obstructive pulmonary disease (COPD). About 30 years previously, he was diagnosed with arterial hypertension and type 2 diabetes mellitus. He had problems with the peripheral circulation, and 10 years earlier necrosis had started to affect his toes and feet. He was treated with percutaneous transluminal angioplasty of the stenotic femoral arteries, in addition to amputation of the right forefoot and the left crus. In his last year, ischemic and infected wounds again developed on his right foot. He also had psoriatic affection of the skin. One year previously, while on vacation abroad, he suffered a myocardial infarction. Coronary angiography (CAG) showed stenosis of the left main artery (LM), the left anterior descendent artery (LAD), and the proximal circumflexus artery (CX), and he was treated with percutaneous coronary intervention (PCI) and stents. EF 25% and reduced right ventricular function. Sinus rhythm and left bundle branch block 174 ms. (Figure 1).
The patient received treatment with an angiotensin-converting enzyme inhibitor, beta-blocker, diuretics, statin, and salicylate and was scheduled implantation with a CRT-D. Before this could be realized, however, he was admitted with ACS with EF dropping to 10% and protracted cardiogenic shock with multiorgan dysfunction. Restenosis was revealed in the stented areas and treated with balloon angioplasty. He slowly recuperated.
About two months later, he suffered another ACS and in addition to severe in-stent restenosis, corresponding to severe stenosis in the distal LM, the ostial LAD, and the proximal CX, a stenosis in the proximal right coronary artery (RCA) was also detected (Figure 2). He was in a poor state and performing PCI or coronary artery bypass grafting (CAGB) posed a very high risk; instead medical treatment was recommended. His condition remained unstable and characterized by angina pectoris, dyspnea and problems with comorbidities. Due to the poor prognosis, a limited level of treatment was decided in consultation with the patient and his family. This decision was re-evaluated on an ongoing basis.
Implantation of a CRT-D was postponed due to septicemia with Staphylococcus aureus, which was cultivated from the blood and from the wound on his right foot. He was administered antibiotic therapy. Three weeks later, all signs of infection had disappeared. However, the leg wound was not completely closed, but the biochemical screenings values were normal. The CRT-D was implanted without complications (an antibacterial envelope was not used). The patient improved, his shortness of breath subsided from NYHA III to NYHA II, and the QRS-duration diminished to 146 ms. (Figure 3).
As the next step, CABG was planned, but had to be postponed due to recidivating septicemia and infection without a recognized focus. Staphylococcus aureus, Staphylococcus epidermidis, and Corynebacterium were cultivated from the blood. Transesophageal echocardiography revealed discrete changes related to a pace lead, no typical vegetations and no valvular involvement. Positron emission tomography-computerized tomography (PET-CT) showed a change in the same area. Specialists were called upon to evaluate the patient, and it was finally concluded that the infection was probably related to the pacemaker, and system extraction was mandated. Percutaneous explantation was performed, 6 weeks after the implantation, by an experienced operator, with simple traction of the leads, and without procedural complications; a few hours later, however, he began to develop shock with falling bloodpressure, and his temperature rose to 38.5. Monitoring echocardiography showed a drop in ejection fraction (EF) from 20% to 5% despite intensive care.He exhibited no pericardial effusion. His condition deteriorated rapidly, and implantation of a new “rescue” CRT was not considered a possibility. In addition, revascularization could have been a solution, but with a very high risk and it was rejected due to his poor condition and the comorbidities. Extracorporeal membrane oxygenation (ECMO) and impella were not an option due to the peripheral vascular disease.He did not respond to vasopressor therapy (norepinephrine) and died within 17 hours of surgery.
Figure 1: ECG before CRT. SR with LBBB 174 ms.
Figure 2: CAG. Stenosis LM 85 %, LAD 95 %, D1 80 %, CX 85 %, RCA 75 %.
Figure 3: ECG after implantation of CRT. QRS 146 ms.
From a short-term and a long-term perspective, increased mortality is seen in patients who have had their CRT explanted without a new one being implanted [7]. Besides, various surgical complications in connection with the explantation may be fatal [8,12]. However, until now, the occurrence of cardiogenic shock a few hours after explantation has not been described in the literature, which is actually surprising since the condition ought to be expected due to the loss of hemodynamic support and the resultant increased dyssynchrony, hypokinesia, and mitral insufficiency [7,13,14]. In this case, the removal of the CRT precipitated acute malignant cardiogenic shock. There are several likely explanations, because due to end stage cardiomyopathy any perturbation (a procedure, co-illness, infection, blood loss, etc.) could have send him down the road to shock. Shock due to sepsis syndrome was unlikely because no bacteria were cultivated, neither from the leads, nor from the generator pocket. Besides, the patient was administered broad-spectrum antibiotics. Cardiogenic shock is associated with high mortality due to the serious underlying cardiac disease and several risk factors that may trigger an additional impairment of cardiac contractility. Reversible causes of cardiogenic shock should be treated immediately in order to increase the patient’s chances of survival. ACS is the most frequent cause of cardiogenic shock and early revascularization is the most important treatment strategy in cardiogenic shock because it is potentially lifesaving [1-3], as when this patient suffered a cardiogenic shock the first time. Unfortunately, the coronary stenosis recurred and CAG revealed high risk, central, and severe three-vessel coronary artery disease including LM-stenosis, placing the patient at high risk for recurrent shock because even a minor change in blood pressure and hemodynamics could lead to a death spiral.
When neither the precipitating factor, nor the underlying disease is treatable, the prognosis is very poor, and the treatment for cardiogenic shock may only protract the foreseeable course of events and inevitable death [1]. This patient had a number of risk factors predisposing to device infection: Diabetes mellitus, COPD, heart failure, skin disorder, and pre-procedural fever. Device-type is an independent risk factor with CRT being most exposed to infection [4-6]. Device infection carries an ominous prognosis and despite risk of fatal complications due to device removal, the recommended treatment consist of early, complete system extraction, prolonged intravenous antibiotic therapy, and biventricular device reimplantation [4,6-8,10]. In this case, however, minor surgery and closed irrigation with antibiotics [15] or protracted antibiotic treatment possibly had been preferable to explantation because, as became evident, the patient depended with his life upon pacing of the left ventricle [6,10]. Had this been discovered in due course, and before removing the CRT, the LV-pacing could had been disabled and stopped and the patient’s reactions observed before a decision to operate or not was taken. Unfortunately, this was not the case.
A high-risk patient with severe ischemic cardiomyopathy had an infected CRT explanted. A few hours later, he developed irreversible cardiogenic shock. It is suggested to disable LV-pacing and monitor clinical response and EF before deciding whether to remove a CRT.
Funding: The author received no specific funding for this work.
Conflicts of Interest: I have no conflicts to disclose.