Case Report: Hypertrophic Cardiomyopathy

Summary:
A 69-year-old male, with a history of stroke, hypertrophic cardiomyopathy, and chronic atrial fibrillation, underwent left hip surgery with oral anticoagulants stopped three days preoperatively. Intubation was performed using Glycopyrrolate 0.2mg, Midazolam 1mg, Fentanyl 200mcg, Sevoflurane, and Succinylcholine 75mg. A PENG block was administered post-induction. Intraoperatively, 1 liter of intravenous fluids and 1 unit of packed red blood cells (PRBC) were transfused during the 2-hour surgery. Central line insertion via the right internal jugular vein was performed. The patient was successfully extubated on the table, and the postoperative period was uneventful.

Article: Comprehensive Insights into Hypertrophic Cardiomyopathy (HCM) and Anesthetic Management Strategies

Introduction

Hypertrophic Cardiomyopathy (HCM) is a rare autosomal dominant myocardial disease characterized by diverse manifestations, including left ventricular hypertrophy (LVH). A subset of HCM patients may develop hypertrophic obstructive cardiomyopathy (HOCM) due to asymmetric septal hypertrophy, leading to left ventricular outflow tract (LVOT) obstruction. This article provides a comprehensive overview of HCM, emphasizing the challenges it poses in anesthetic management and presenting a systematic approach for perioperative care.

Hypertrophic Cardiomyopathy: A Brief Overview

Epidemiology

HCM’s prevalence ranges from 0.2-0.5% in the general population, with some cases identified through cardiac magnetic resonance imaging in seemingly healthy individuals.

Presentation

While many HOCM patients are asymptomatic, symptoms may include chest pain, dyspnea, syncope, or palpitations. Acute hemodynamic instability can also occur due to exacerbation of LVOT obstruction.

Diagnosis

Key diagnostic tools include echocardiography, which helps assess LV morphology, gradients, and dynamic changes during interventions. Classification is based on the degree of LVOT obstruction.

Anesthetic Management of Hypertrophic Cardiomyopathy

Preoperative Evaluation

Disease Severity Assessment:

• Evaluate symptoms, functional status, and personal/family cardiac history.
• Assess for cardiac and respiratory symptomatology, strokes, heart failure, and rhythm disturbances.

Physical Examination:

• Dynamically assess murmurs using various maneuvers.
• Monitor changes in murmur intensity to gauge physiological impact.

Baseline Investigations:

• Conduct baseline ECG and echocardiographic assessment.
• Identify red flags indicating severe HCM and associated complications.

Medication Continuation:

• Instruct patients to continue beta-blockers, calcium channel blockers, and disopyramide.
• Emphasize perioperative hydration.

Certainly! Here’s a table summarizing the information:

Intraoperative Management

Hemodynamic Goals:

• Align goals with aortic stenosis, considering the dynamic nature of LVOT obstruction.
• Mitigate factors exacerbating LVOT obstruction.

Monitoring:

• Utilize standard ASA monitors and consider additional monitoring for high-risk cases.
• Transesophageal Echocardiography (TEE) may be beneficial in major surgeries.

Neuraxial Anesthesia:

• Prefer slow epidural titration over spinal anesthesia to maintain preload and afterload.
• Minimize sympathetic stimulation during induction.

Fluid Management:

• Consider fluid loading to ensure adequate preload.
• Use diuretics cautiously to avoid exacerbating LVOT obstruction.

Inotropes and Vasopressors:

• Preferably avoid inotropes; maintain normotension.
• Use phenylephrine for a favorable hemodynamic profile.

Sympathetic Stimulation:

• Be vigilant during intubation, surgical stimulus, and pain.
• Maintain normal sinus rhythm; treat arrhythmias promptly.

Noradrenaline Avoidance in LVOTO

Alpha-Adrenergic Effects:

• Noradrenaline induces vasoconstriction, increasing afterload and worsening LVOT obstruction.

Increased Myocardial Work:

• Noradrenaline raises contractility and heart rate, intensifying LVOT obstruction.

Potential for Hemodynamic Instability:

• Vasoconstriction may lead to elevated blood pressure, posing risks in compromised cardiovascular systems.

Alternative Agents:

• Phenylephrine, with primarily alpha effects, is a preferred alternative in LVOTO.

Epinephrine and calcium should be avoided in Left Ventricular Outflow Tract Obstruction (LVOTO) due to their potential to exacerbate the condition and worsen hemodynamic instability.

Epinephrine:

• Increased Inotropy: Epinephrine is known for its positive inotropic effects, which can enhance the force of cardiac contractions.
• Vasoconstriction: It also causes vasoconstriction, leading to increased afterload, which is problematic in LVOTO where there is already obstruction of blood flow during ejection.

Calcium:

• Inotropic Effect: Calcium is essential for myocardial contractility. Supplementing calcium can increase the force of contraction.
• Potential for Increased LVOTO: This increased contractility can exacerbate LVOTO by intensifying the obstruction during systole.

cal context.

Conclusion

A systematic approach to anesthetic management is crucial for optimal outcomes in HCM patients. By carefully evaluating disease severity, utilizing appropriate monitoring, and avoiding agents that exacerbate LVOT obstruction, anesthesiologists can contribute to the safe perioperative care of individuals with hypertrophic cardiomyopathy. Individualized care, in consultation with the medical team, ensures the best possible outcomes for these challenging cases.