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Case Presentation
A 75-year-old female patient with medical history of nonischemic heart failure with reduced ejection fraction (HFrEF) with left ventricular ejection fraction (LVEF) of 35%, hypertension, and diabetes mellitus presented with worsening shortness of breath on exertion and bilateral leg swelling. She had New York Heart Association (NYHA) functional class III symptoms. At home, she has been on optimal guideline-directed medical therapy (GDMT) consisting of valsartan-sacubitril, carvedilol, spironolactone, empagliflozin, and furosemide. She has been adherent with her all medications since the diagnosis of HFrEF was made 6 months ago.
On physical examination, blood pressure was 104/62 mmHg and pulse rate was 58 bpm. A grade 2/6 holosystolic murmur was heard at the apex, and a grade 1/6 crescendo-decrescendo systolic murmur was heard at the base. Bibasilar crackles, jugular venous distention, and significant bilateral lower extremity pitting edema were also present. Otherwise, the physical exam was unremarkable. Electrocardiogram showed sinus rhythm and left bundle branch block (LBBB) with QRS duration of 155 milliseconds. Laboratory studies were unremarkable except elevated B-type natriuretic peptide.
Echocardiogram showed an ejection fraction of 30%, elevated left ventricular filling pressures, mild to moderate mitral regurgitation, and mild aortic stenosis. The patient was started on intravenous furosemide to optimize her volume status. The heart failure team continued to follow her closely, and once euvolemia was achieved, she was planned for cardiac resynchronization therapy (CRT) implantation before the discharge since CRT is associated with improved LVEF, reduced symptoms, and improved survival rates in patients with LVEF less than 35%, NYHA functional class II to IV symptoms, and LBBB. The patient underwent CRT placement successfully before discharge, was followed up in the heart failure clinic after discharge, and reported improvement in her symptoms and exercise tolerance.
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KEY POINTS
Pacemakers provide appropriate heart rate response for cardiac functioning and hemodynamic effects.
Implantable cardioverter-defibrillator provides high-energy shock or antitachycardia therapy for termination of malignant arrhythmias.
CRT improves cardiac dyssynchrony to help left ventricular function.
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Cardiac implantable electronic devices (CIEDs) are specialized treatment for detection and treatment of tachy- or bradyarrhythmias. This chapter addresses the knowledge about use, indications, and complications associated with CIEDs.
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Cardiac pacemakers are effective treatments for a variety of bradyarrhythmias by providing appropriate heart rate response to reestablish effective circulation. Pacemakers are mechanical devices that generate electrical impulses propagated via 1 or more pacing wires to promote the regular contraction of the atria and/or the ventricles. They can be temporary or permanent.
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The pacemaker senses electrical signals from cardiac chambers and responds by inhibiting or triggering pacing. Various programming algorithms allow further control of pacing mode and rate. Most modern pacemakers capture and store a breadth of ...