Lab/ECG/Xray Rounds The EM Resident Provisionally Known as Sean Caine CCFP-EM March 5, 2008

Case 29 yo male presents with severe lightheadedness and palpitations during sexual activity Symptoms persisted x min Spontaneous resolution

Case continued Additional hx: 2 prev visits to ED in past month for similar symptoms 1 st episode Lightheaded while mowing the lawn D/C home from ED after ECG and normal labs 2nd episode Syncopal watching TV Admitted for observation Had serial cardiac enzymes and cardiac monitoring Discharged home after negative work up Instructed to f/u with GP

Case Normal vitals and physical exam ECG is obtained….

Hypertrophic Cardiomyopathy (HCM)

Objectives Background Background Etiology Etiology Pathophysiology Pathophysiology Clinical Presentation Clinical Presentation ECG Findings ECG Findings Treatment Treatment

Thank you… Adam Davidson and Jeff Booker

Background aka Idiopathic hypertrophic subaortic stenosis, obstructive cardiomyopathy aka Idiopathic hypertrophic subaortic stenosis, obstructive cardiomyopathy Notable cause of sudden cardiac death among athletes Notable cause of sudden cardiac death among athletes Accounting for 2-36% SCD among athletes Accounting for 2-36% SCD among athletes Prevalence of % of general population Prevalence of % of general population Accounts for up to 60% of unexplained LVH Accounts for up to 60% of unexplained LVH MOST COMMON genetic cardiovascular disorder MOST COMMON genetic cardiovascular disorder

Background SCD most common for those <35 yrs of age 1 SCD most common for those <35 yrs of age 1 –No age is immune from SCD Annual mortality rates as high as 3-6% 3 Annual mortality rates as high as 3-6% 3

Etiology 30-50% due to familial inheritance 1, % due to familial inheritance 1,5 Autosomal dominant inheritance with variable penetration Autosomal dominant inheritance with variable penetration mutations of 1 of 11 possible genes encoding proteins for myocardial sarcomere mutations of 1 of 11 possible genes encoding proteins for myocardial sarcomere

35% 15%

Pathophysiology Hypertrophied, nondilated left ventricle in the absence of another cause Hypertrophied, nondilated left ventricle in the absence of another cause Histology: Histology: –Hypertrophied muscle cells –Cellular disorganization in whorled pattern –Abnormal fibrous tissue –Scarring mimics healed MI

Schematic Asymmetric septal hypertrophy (ASH) Asymmetric septal hypertrophy (ASH) Systolic motion of MV anteriorleaflet (SAM) Systolic motion of MV anteriorleaflet (SAM) LVOT gradient LVOT gradient Mitral regurgitation (MR) Mitral regurgitation (MR)

2 Chamber Echo DiastoleSystole

Morphologic Variants of HCM

Clinical Presentation Can be completely asymptomatic Can be completely asymptomatic Presenting Symptoms Presenting Symptoms –Dyspnea –Exercise intolerance –Dizziness –Chest pain –Presyncope/syncope –Sudden Cardiac Death

Clinical Presentation Average age at diagnosis is yrs Average age at diagnosis is yrs 2% diagnosed before the age of 5 2% diagnosed before the age of 5 7% before the age of 10 7% before the age of 10

Key features on history Previous hx of syncope Family history of SCD or early onset of symptoms

Physical Examination S4 gallop S4 gallop Harsh crescendo-decrescendo midsystolic murmur loudest at apex Harsh crescendo-decrescendo midsystolic murmur loudest at apex – LOUDER with valsalva and standing –SOFTENS with lying, squatting, or isometric exercise Bifid arterial pulse,double/triple apical impulse,palpable atrial gallop Bifid arterial pulse,double/triple apical impulse,palpable atrial gallop

THE ECG Abnormal in 90% Abnormal in 90% ECG Findings LVH: 30% LVH: 30% – and associated ST and T wave changes Deep NARROW Q waves (typically I, aVL, V5, V6) Deep NARROW Q waves (typically I, aVL, V5, V6) Left atrial enlargement: 25-50% Left atrial enlargement: 25-50%

30 yo male with 20 min of lightheadedness running to bus

31 yo female syncope preceded by palpitations during physical activity

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Diagnosis Ultimately made by doppler Echo Ultimately made by doppler Echo

Complications Increased incidence of WPW Increased incidence of WPW Chronic or paroxysmal afib (10-40%) Chronic or paroxysmal afib (10-40%) Moderate risk for infective endocarditis Moderate risk for infective endocarditis SCD SCD

Pharmacotherapy β blockers are first line β blockers are first line –Verapamil or disopyramide prescribed with caution when β blocker poorly tolerated Afterload reducing agents with systolic dysfunction/CHF Afterload reducing agents with systolic dysfunction/CHF –ACEI, diuretics, digoxin Amiodarone should be used for ventricular dysrhythmias Amiodarone should be used for ventricular dysrhythmias Avoid nitrates (decrease preload and LVOT) Avoid nitrates (decrease preload and LVOT)

Nonpharmacologic therapy Septal myomectomy Septal myomectomy Alcohol septal ablation Alcohol septal ablation ICD ICD

Take Home Points Be suspicious of unexplained LVH on ECG Be suspicious of unexplained LVH on ECG –Especially in symptomatic patients Think HCM with narrow qwaves in lateral leads Think HCM with narrow qwaves in lateral leads

References Ramaraj R. Hypertrophic Cardiomyopathy: Etiology, Diagnosis, Treatment. Cardiology in Review. 2008; 14(4): Dovgalyuk J, Holstege C, Mattu A, Brady WJ. The electrocardiogram in the patient with syncope. American Journal of Emergency Medicine. 2007; 25: Kelly BS, Mattu A, Brady WJ. Hypertrophic cardiomyopathy: electrocardiographic manifestations and other important considerations for the emergency physician. American Journal of Emergency Medicine. 2007; 25: Jouriles NJ. Hypertrophic Cardiomyopathy. Marx: Rosens Emergency Medicine: Concepts and Clinical Practice. 6 th ed Niemann JT. Hypertrophic Cardiomyopathy. Emergency Medicine: A comprehensive study guide. 6th ed. 2004:

Sudden Cardiac Death Risk factors Risk factors Sustained VT Sustained VT Recurrent syncope (esp w/exertion) Recurrent syncope (esp w/exertion) Family hx of 1 or more SCD Family hx of 1 or more SCD Extreme LVH (>30mm wall thickness) Extreme LVH (>30mm wall thickness) LVOT gradient >30mmHg LVOT gradient >30mmHg Abnormal BP response to exercise Abnormal BP response to exercise Nonsustained VT ambulatory monitor Nonsustained VT ambulatory monitor 0-1 RF = 1% annual SCD rate 0-1 RF = 1% annual SCD rate 2 or more= increased risk of SCD and prophylactic ICD should be considered 2 or more= increased risk of SCD and prophylactic ICD should be considered

Distinguishing hypertrophic cardiomyopathy (HCM) from "Athlete's Heart" ParameterFindings in HCMFindings in Athlete's Heart LV wall thickness and morphology Can be >16 mm; can be heterogeneous or asymmetric across segments Typically <16 mm, especially in women; symmetric Diastolic LV cavity<45 mm (except in late, dilated phase)>55 mm LA sizeEnlargedNormal LV diastolic filling pattern Impaired relaxation (E:A ratio <1, prolonged diastolic deceleration time) Normal Response to deconditioning NoneLV wall thickness decreases EKG findings Very high QRS voltages; Q waves; deep negative T waves Criteria for LVH but without unusual features Family history of HCM Present (except de novo mutations)Absent LV: left ventricle; LA: left atrium; LVH: left ventricular hypertrophy. Adapted from Maron, BJ, Pellicia, A, Spirito, P. Circulation 1995; 91:1596.

25 yo male severe palpitations, lightheadedness, presyncope playing basketball