Coronary Embolization in Hypertrophic Cardiomyopathy With Left Ventricular Apical Aneurysm Ankur Kalra, MDa, Martin S. Maron, MDb, Ethan J. Rowin, MDb, Timothy K. Colgan, MDc, John R. Lesser, MDa, and Barry J. Maron, MDa,* Patients with left ventricular apical aneurysms represent a unique patient subgroup in the broad clinical spectrum of hypertrophic cardiomyopathy (HC) associated with the risk for sudden death, heart failure, and peripheral thromboembolism. Routine chronic anticoagulation has not been a standard recommendation for these patients. We present a 36-year-old patient with HC with features of acute coronary syndrome, likely secondary to coronary thromboembolism as a complication of left ventricular apical aneurysm. Our experience with this patient raises consideration for prophylactic anticoagulant therapy for this unusual subset of patients with HC. Ó 2015 Elsevier Inc. All rights reserved. (Am J Cardiol 2015;115:1318e1319) Patients with hypertrophic cardiomyopathy (HC) and left ventricular (LV) apical aneurysms represent an underappreciated subset within the heterogeneous clinical spectrum of HC but with important management implications.1,2 Among the adverse disease complications is the underrecognized risk for peripheral thromboembolism, potentially preventable with prophylactic anticoagulation therapy. Case Report A 36-year-old man with HC and LV apical aneurysm and a prophylactic implantable cardioverteredefibrillator presented with a clinical scenario consistent with acute coronary syndrome. He complained of jaw and chest pain, diaphoresis, and presyncope, triggered by running on a treadmill. Twelvelead electrocardiogram showed diffuse deep T-wave inversion, most prominent in the lateral precordial leads. Cardiac troponin I was 0.69 ng/ml on admission and peaked at 0.84 ng/ml. Coronary arteriography and computed tomography angiogram (CTA) excluded obstructive atherosclerotic coronary narrowing and plaque rupture (Figure 1). A thrombus was identified in the distal right coronary artery (posterolateral branch of the posterior descending artery) and was immediately removed by aspiration thrombectomy, followed by balloon angioplasty.3 An extensive hypercoagulable workup proved normal, including factor V Leidin, protein C and S, and homocysteine levels; anticardiolipin antibodies; dilute Russell viper venom time; and hexagonalphase phospholipid neutralization assay. Two-dimensional echocardiogram demonstrated anterior ventricular septal thickness of 14 mm. Systolic anterior motion of the mitral valve was absent and continuous-wave a The Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation at Abbott-Northwestern Hospital, Minneapolis, Minnesota; b Hypertrophic Cardiomyopathy Center, Division of Cardiology, Tufts Medical Center, Boston, Massachusetts; and cAdvanced Cardiovascular Specialists LLP, Beaumont, Texas. Manuscript received January 21, 2015; revised manuscript received and accepted February 3, 2015. See page 1319 for disclosure information. *Corresponding author: Tel: (612) 863-3996; fax: (612) 863-3875. E-mail address: [email protected]; [email protected] (B.J. Maron).

0002-9149/15/$ - see front matter Ó 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.amjcard.2015.02.016

Doppler interrogation of the LV outflow tract yielded normal velocities of 1.2 m/s at rest and 1.4 m/s with Valsalva maneuver. Left atrial dimension was 39 mm; LV end-diastolic dimension was 50 mm and ejection fraction was 74%. Cardiovascular magnetic resonance (CMR) imaging with intravenous contrast injection of gadolinium (Figure 1) and CTA (Figure 1) showed an LV apical aneurysm, 2 cm in transverse dimension, with transmural late gadolinium enhancement of the aneurysmal rim (consistent with myocardial scarring) extending into adjacent myocardium. An intraventricular clot was not identified by CTA, echocardiography, or CMR. Histopathology of the aspirated clot showed alternating lines of red blood cells, platelets, and fibrin (lines of Zahn), diagnostic of a thrombus (Figure 1), and without evidence of atherosclerotic plaque (i.e., absence of cholesterol clefts, foam cells, or calcification). The patient was discharged uneventfully on warfarin for prevention of stroke. Discussion Thin-walled, akinetic/dyskinetic LV apical aneurysms occur in about 2% of patients with HC and are more reliably identified by tomographic, highespatial resolution CMR imaging than with 2-dimensional echocardiogram.2 The clinical course of this subgroup of patients with HC is variable but can be associated with severe progressive heart failure symptoms and arrhythmic sudden death with monomorphic ventricular tachycardia emanating from areas of myocardial scarring.4 The akinetic/dyskinetic aneurysm in HC also provides the structural and functional basis for intracavitary thrombus formation. In the largest series of patients with HC with LV apical aneurysms, 2 of 28 patients experienced thromboembolic events (similar to the present case), and in 2 others without events, a thrombus was fortuitously identified within the aneurysm by CMR.2 These 4 patients had relatively large aneurysms (3 cm in transverse dimension) and were in sinus rhythm at the time their stroke occurred or when the thrombus was identified.2 www.ajconline.org

Case Report/HC With LV Apical Aneurysm

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Figure 1. (A) Curved multiplanar reconstructed images from CTA demonstrating normal right coronary artery anatomy without evidence of coronary atherosclerosis (arrowheads). (B) End-diastolic 2-chamber long-axis CMR images of thin-walled, LV apical aneurysm after intravenous contrast injection of gadolinium showing transmural late gadolinium enhancement (consistent with myocardial fibrosis) of the aneurysmal rim (arrow) extending into adjacent myocardium and without evidence of an intraventricular thrombus. (C) Coronal section from computed tomographic scan demonstrating LV apical aneurysm measuring 2 cm in transverse dimension (arrow), without evidence of an intraventricular thrombus. (D) Histopathologic section of thrombus removed from the right coronary artery (by aspiration thrombectomy) demonstrating alternating lines of red blood cells, platelets, and fibrin (lines of Zahn; arrowheads).

The aneurysm in the present case was smaller (2 cm in diameter) but nevertheless represented the only logical site of thrombus formation, given normal left atrial size and absence of atrial fibrillation either before or during the embolic event. Therefore, we propose that the most reasonable conclusion is that the thrombus retrieved by thrombectomy in our patient most likely developed in the apical dyskinetic aneurysm, ultimately embolized to the right coronary artery, causing the patient’s cardiac event. Thromboembolism in patients with HC with LV apical aneurysm is an uncommon but potentially devastating event. This possibility raises consideration for more systematic prophylactic anticoagulation in this important and newly described subset of patients with HC, independent of the size of the aneurysm.2 The decision to initiate long-term anticoagulation in such patients with HC with LV apical aneurysm should be made on a case-by-case basis.

Disclosures The authors have no conflicts of interest to disclose. 1. Maron BJ, Ommen SR, Semsarian C, Spirito P, Olivotto I, Maron MS. Hypertrophic cardiomyopathy: present and future, with translation into contemporary cardiovascular medicine. J Am Coll Cardiol 2014;64: 83e99. 2. Maron MS, Finley JJ, Bos JM, Hauser RH, Manning WJ, Haas TS, Lesser JR, Udelson JE, Ackerman MJ, Maron BJ. Prevalence, clinical significance, and natural history of left ventricular apical aneurysms in hypertrophic cardiomyopathy. Circulation 2008;118:1541e1549. 3. Hernández F, Pombo M, Dalmau R, Andreu J, Alonso M, Albarrán A, Velázquez MT, Tascón JC. Acute coronary embolism: angiographic diagnosis and treatment with primary angioplasty. Catheter Cardiovasc Interv 2002;55:491e494. 4. Lim KK, Maron BJ, Knight BP. Successful catheter ablation of hemodynamically unstable monomorphic ventricular tachycardia in a patient with hypertrophic cardiomyopathy and apical aneurysm. J Cardiovasc Electrophysiol 2009;20:445e447.

Coronary embolization in hypertrophic cardiomyopathy with left ventricular apical aneurysm.

Patients with left ventricular apical aneurysms represent a unique patient subgroup in the broad clinical spectrum of hypertrophic cardiomyopathy (HC)...
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