Patient Presentation
A 76-year-old male with a medical history of hypertension, Type 2 diabetes mellitus, and dyslipidemia presented to the emergency department following a six-day prodrome of vomiting, diarrhea, and progressive dizziness. In the 48 hours preceding admission, he experienced two syncopal episodes, the second accompanied by minor cranial trauma. Upon arrival, he was found to have profound bradycardia (heart rate of 32 beats per minute), hypotension, signs of peripheral hypoperfusion, and an acute confusional state. Shortly after presentation, he sustained a cardiac arrest. Return of spontaneous circulation was achieved after a single cycle of advanced cardiovascular life support.
Initial Evaluation and Diagnostic Workup
An initial 12-lead electrocardiogram (ECG) demonstrated complete atrioventricular block (CAVB) with a ventricular escape rhythm at 32 bpm. The rhythm exhibited a right bundle branch block (RBBB) pattern with concomitant left anterior fascicular block (LAFB) and ST-segment elevations in leads V2 to V4, which extended to V6 shortly afterward. Two brief Stokes–Adams attacks were witnessed during the early course.
Emergency Interventions
The patient underwent emergent stabilization with orotracheal intubation, temporary transvenous pacing achieving a ventricular rate of 70 bpm, and placement of a Swan–Ganz catheter. Hemodynamic monitoring revealed a cardiac output of 2.1 L/min, a cardiac index of 1.1 L/min/m², systemic vascular resistance index of 2235 dyn•s/cm⁵, pulmonary capillary wedge pressure of 17 mmHg, cardiac power output of 0.58 W, and pulmonary artery pressures of 36/22/27 mmHg (systolic/diastolic/mean). Pharmacologic support was initiated with norepinephrine and dobutamine based on these findings.
Coronary Angiography and Revascularization
Urgent coronary angiography revealed diffuse coronary atherosclerosis with a severely stenotic proximal left anterior descending artery (LAD) demonstrating TIMI 2 flow, a moderately developed left circumflex artery (LCx) with 90% proximal obstruction (also TIMI 2 flow), and a right dominant coronary artery (RCA) without significant disease. Percutaneous coronary intervention (PCI) was performed using a paclitaxel-coated balloon in the LAD and a drug-eluting stent (Onyx 3.0/18 mm) in the LCx. Post-PCI, both vessels achieved TIMI 3 flow. The CAVB resolved immediately following revascularization, although RBBB and LAFB remained.
Cardiac Function and Hospital Course
Echocardiographic evaluation revealed severe left ventricular systolic dysfunction with an ejection fraction (LVEF) of 25%. Regional wall motion abnormalities included akinesia of the midapical anterior, lateral, septal, anteroseptal, and inferolateral segments. At 36 hours postadmission, the patient developed atrial fibrillation, recurrent episodes of CAVB, and a severe low cardiac output state. Persistent left ventricular dysfunction at 10 days postadmission led to the implantation of a cardiac resynchronization therapy device with defibrillator (CRT-D).
Complications and Clinical Outcome
Following initial stabilization, the patient showed gradual clinical improvement, enabling initiation and titration of guideline-directed medical therapy for heart failure with reduced ejection fraction (HFrEF). However, due to the severity of his initial illness and prolonged intensive care unit (ICU) stay, he developed ICU-acquired myopathy, dysphagia, peripheral neuropathy, and sarcopenia. These complications necessitated placement of a percutaneous endoscopic gastrostomy (PEG) tube and prolonged rehabilitation. Despite efforts, the patient experienced septic shock due to healthcare-associated pneumonia three weeks later, which progressed rapidly to multiorgan failure. He died on the 60th day of hospitalization.
