Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 
  Home Print this page Email this page Small font sizeDefault font sizeIncrease font size Users Online: 970  

 
   Table of Contents      
CASE REPORT
Year : 2017  |  Volume : 16  |  Issue : 3  |  Page : 251-254

An uncommon variant of an uncommon disease: A Caucasian adolescent with apical hypertrophic cardiomyopathy diagnosed with myocardial perfusion imaging


1 Department of Internal Medicine, St. John Hospital and Medical Center, Detroit, MI, USA
2 Department of Nuclear Medicine, Beaumont Health, Royal Oak, MI, USA
3 Department of Cardiology, St. John Hospital and Medical Center, Detroit, MI, USA

Date of Web Publication30-May-2017

Correspondence Address:
Rami Kassem Zein
Department of Cardiology, St. John Hospital and Medical Center, 19251 Mack Avenue, Suite 335, GPW, MI 48236
USA
Login to access the Email id


DOI: 10.4103/1450-1147.207285

PMID: 28670188

Rights and Permissions
   Abstract 

Apical hypertrophic cardiomyopathy (ApHCM) is a subtype of HCM. This variant is more common in the Asian population when compared to North American patients. Patients may present with arrhythmias, heart failure, myocardial infarction, chest discomfort, fatigue, and presyncope or syncope. Initial evaluation requires electrocardiogram and two-dimensional echocardiogram. T-wave inversion in the precordial leads as well as hypertrophy of the left ventricle is hallmarks of the disease. Cardiac magnetic resonance (CMR) imaging is the most specific and sensitive imaging modality. In patients with contraindications for CMR, myocardial perfusion imaging (MPI) has been described to have diagnostic characteristics for ApHCM. MPI images demonstrating a “solar polar” map pattern and increased apical tracer uptake in single-photon emission computed tomography horizontally and vertical long-axis slices are consistent with the diagnosis of ApHCM. Herein, we present a case of a Caucasian adolescent female who underwent a cardiac screening to rule out hypertrophic obstructive cardiomyopathy. Initially, the patient was unable to undergo CMR, and an MPI was utilized to assist with the diagnosis of ApHCM.

Keywords: Apical, cardiomyopathy, hypertrophic, myocardial perfusion imaging, myocardial perfusion, solar polar map


How to cite this article:
Zein RK, Al-Faham Z, Mouabbi JA, Daher ER. An uncommon variant of an uncommon disease: A Caucasian adolescent with apical hypertrophic cardiomyopathy diagnosed with myocardial perfusion imaging. World J Nucl Med 2017;16:251-4

How to cite this URL:
Zein RK, Al-Faham Z, Mouabbi JA, Daher ER. An uncommon variant of an uncommon disease: A Caucasian adolescent with apical hypertrophic cardiomyopathy diagnosed with myocardial perfusion imaging. World J Nucl Med [serial online] 2017 [cited 2021 Jan 18];16:251-4. Available from: http://www.wjnm.org/text.asp?2017/16/3/251/207285


   Introduction Top


Apical hypertrophic cardiomyopathy (ApHCM) is a subtype of HCM, which is characterized by asymmetric myocardial hypertrophy of the apex of the left ventricle. These patients do not have a classical left ventricular (LV) outlet obstruction but may have mid-ventricular obstruction that can manifest similar symptoms to that of hypertrophic obstructive cardiomyopathy (HOCM).[1] Apical HCM develops more common in the Asian population.[2],[3] In this case, we will review the clinical characteristics of ApHCM and correlate it with different radiographic modalities specifically myocardial perfusion imaging (MPI).


   Case Report Top


An asymptomatic 15-year-old Caucasian female with no significant medical history underwent a yearly physical examination before participation in sports. She has a history of orthopedic surgery with an unknown metal implant. The patient denies any family history for sudden cardiac death, seizure activity, or syncopal episodes. The patient denies any syncope, loss of consciousness, palpitations, or chest discomfort. Physical examination findings were within normal limits with no extra heart sounds, murmurs, rubs, or gallops. The patient electrocardiography demonstrated normal sinus rhythm with LV hypertrophy and T-wave inversion in the inferolateral leads [Figure 1]. The patient was referred for a two-dimensional (2D) echocardiogram (ECHO) [Figure 2], which revealed hypokinesia of the anterior apical segment. The right ventricular apex appeared either foreshortened or hypoplastic. There was no evidence of aortic stenosis. Due to the patients' orthopedic implant, she underwent exercise stress Tc-99m sestamibi MPI. The MPI demonstrated apical thickening with a focal hotspot on the rest images [Figure 3]a,[Figure 3]b,[Figure 3]c. Gated image also revealed apical bulging and tardokinesis with a normal ejection fraction of 67%. It was later confirmed the patient did not have any metal implant and underwent cardiac magnetic resonance (CMR) [Figure 4]. This patient was diagnosed with ApHCM based on the electrocardiogram (ECG), 2D ECHO, MPI imaging, and later CMR.
Figrure 1: The electrocardiogram demonstrates normal sinus rhythm with left ventricular hypertrophy. There is a marked ST abnormality with T-wave inversion in leads II, III, arteriovenous fistula, and V3-V6. The T-wave inversion in our patient follows a characteristic pattern of inferolateral pathology

Click here to view
Figure 2: The two-dimensional echocardiogram displayed above demonstrates apical hypertrophy with apical obliteration with systole. The overall global left ventricular function is normal. There is normal right ventricular chamber size and wall thickness

Click here to view
Figure 3: The single-photon emission computed tomography images: (a) Septal-lateral. Rest (top images) and stress imaging (bottom images) demonstrate unusual morphology with the apex appearing prominent. The perfusion at the apex appears decreased on stress compared to rest; however, this is likely an artifact. (b) Inferior-superior. Rest (top images) and stress imaging (bottom images) demonstrate unusual morphology with the apex appearing prominent. The perfusion at the apex appears decreased on stress compared to rest; however, this is likely an artifact. (c) 17- segment bullseye model. Rest (middle) and stress imaging (left) demonstrate the “solar polar map” and is characteristic of apical hypertrophy

Click here to view
Figure 4: Cardiac magnetic resonance images in the sagittal view showing end diastole (left side) and short- axis view in end systole (right side). The apical myocardial thickening extends approximately 3 cm in length and is between 3.5 and 4 cm in thickness

Click here to view



   Discussion Top


ApHCM is an uncommon subtype of HCM, which is characterized by asymmetric myocardial hypertrophy of the apex of the left ventricle. ApHCM is a more common variant that occurs in Asians than non-Asians, with the prevalence reported to be as high as 41% of the HCM patients in China [2] and in 15% of HCM patients in Japan.[3] Interestingly enough, in non-Asian populations, reports suggest a prevalence between 1% and 3% of HCM patients.[3],[4],[5] The pathophysiology is thought to be associated with sarcomere gene mutations.[6] However, a direct genetic link has not been established. Patients may present asymptomatic during screenings like in our patient versus symptomatic. Symptoms may include arrhythmias such as atrial fibrillation, ventricular fibrillation, fatigue, shortness of breath, and heart failure. Patients may also present with presyncope or syncope.[1],[2],[4],[7]

ApHCM has a better mortality prognosis compared to HOCM and other variants. In a study done by Eriksson et al. in 2002, a group of 105 patients with ApHCM were followed for 13.6 years. The total cardiovascular mortality rate was 1.9%. These patients had atrial fibrillation as the most common complication. Following the completion of that study, ApHCM in the North American patients did not have an association with sudden cardiac death.[7]

Work-up of ApHCM begins with obtaining an ECG. Our patient presented with the classical ECG pattern of giant negative T-waves in the precordial leads (V2-V6).[2] A study conducted by Cianciulli et al. demonstrated 20/20 patients with confirmed ApHCM as having giant T-wave inversion in the precordial leads. The diagnosis can be confirmed with imaging modalities, specifically, 2D ECHO, computed tomography, or CMR.[8],[9] However, in our case, the ability to initially utilize CMR was contraindicated with a suspicion for an orthopedic implant.

The indication for MPI to characterize HCM is not well described. ECHO and CMR have both been described in the literature to be the most sensitive and specific imaging modalities. Nevertheless, the use of MPI in cases where CMR is contraindicated may be a helpful tool in the diagnosis of ApHCM. Previous studies of stress MPI in patients with ApHCM have demonstrated normal to reversible apical perfusion defects along with normal coronary arteries.[8] Our patient demonstrated characteristic ECG abnormalities in association with “solar polar” map pattern and increased apical tracer uptake in single-photon emission computed tomography horizontally and vertical long-axis slices that are consistent with the diagnosis of ApHCM.[8],[10] The apical hypertrophy produces a focal hotspot, with apparent decreased intensity in the mid and basal segments, which is accentuated on the resting images due to loss of resolution from a decreased count rate. On the stress images, this effect is minimized with a three-fold higher count rate which results in improved resolution.

The polar map of the resting images [Figure 3]c also reflects this perfusion artifact, producing apparent reversibility. This polar plot appearance is colloquially known as a “solar polar map” and is characteristic of apical hypertrophy. The MPI appearance in concordance with ECG findings is of diagnostic value regarding the evaluation of ApHCM. Using MPI as a modality can be invaluable when a patient cannot undergo CMR.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
   References Top

1.
Sakamoto T. Apical hypertrophic cardiomyopathy (apical hypertrophy): An overview. J Cardiol 2001;37 Suppl 1:161-78.  Back to cited text no. 1
[PUBMED]    
2.
Ho HH, Lee KL, Lau CP, Tse HF. Clinical characteristics of and long-term outcome in Chinese patients with hypertrophic cardiomyopathy. Am J Med 2004;116:19-23.  Back to cited text no. 2
[PUBMED]    
3.
Kitaoka H, Doi Y, Casey SA, Hitomi N, Furuno T, Maron BJ. Comparison of prevalence of apical hypertrophic cardiomyopathy in Japan and the United States. Am J Cardiol 2003;92:1183-6.  Back to cited text no. 3
[PUBMED]    
4.
Maron MS, Finley JJ, Bos JM, Hauser TH, Manning WJ, Haas TS, et al. Prevalence, clinical significance, and natural history of left ventricular apical aneurysms in hypertrophic cardiomyopathy. Circulation 2008;118:1541-9.  Back to cited text no. 4
[PUBMED]    
5.
Klues HG, Schiffers A, Maron BJ. Phenotypic spectrum and patterns of left ventricular hypertrophy in hypertrophic cardiomyopathy: Morphologic observations and significance as assessed by two-dimensional echocardiography in 600 patients. J Am Coll Cardiol 1995;26:1699-708.  Back to cited text no. 5
[PUBMED]    
6.
Arad M, Penas-Lado M, Monserrat L, Maron BJ, Sherrid M, Ho CY, et al. Gene mutations in apical hypertrophic cardiomyopathy. Circulation 2005;112:2805-11.  Back to cited text no. 6
    
7.
Eriksson MJ, Sonnenberg B, Woo A, Rakowski P, Parker TG, Wigle ED, et al. Long-term outcome in patients with apical hypertrophic cardiomyopathy. J Am Coll Cardiol 2002;39:638-45.  Back to cited text no. 7
[PUBMED]    
8.
Cianciulli TF, Saccheri MC, Masoli OH, Redruello MF, Lax JA, Morita LA, et al. Myocardial perfusion SPECT in the diagnosis of apical hypertrophic cardiomyopathy. J Nucl Cardiol 2009;16:391-5.  Back to cited text no. 8
    
9.
Pons-Lladó G, Carreras F, Borrás X, Palmer J, Llauger J, Bayés de Luna A. Comparison of morphologic assessment of hypertrophic cardiomyopathy by magnetic resonance versus echocardiographic imaging. Am J Cardiol 1997;79:1651-6.  Back to cited text no. 9
    
10.
Ward RP, Pokharna HK, Lang RM, Williams KA. Resting “Solar Polar” map pattern and reduced apical flow reserve: characteristics of apical hypertrophic cardiomyopathy on SPECT myocardial perfusion imaging. J Nucl Cardiol 2003;10:506-12.  Back to cited text no. 10
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4]


This article has been cited by
1 Case 3: A Rare Cause of Syncope in an Adolescent Boy
Yalile Perez,Ruchi Gupta,Richard Mazzaccaro
Pediatrics in Review. 2020; 41(9): 489
[Pubmed] | [DOI]
2 Apical hypertrophic cardiomyopathy with subendocardial late gadolinium enhancement in an adolescent
Simona Boroni Grazioli,Marc-Philip Hitz,Inga Voges
Cardiology in the Young. 2020; : 1
[Pubmed] | [DOI]
3 Apical variant hypertrophic cardiomyopathy “multimodality imaging evaluation”
Gary Huang,Shaimaa A. Fadl,Stan Sukhotski,Manuela Matesan
The International Journal of Cardiovascular Imaging. 2019;
[Pubmed] | [DOI]



 

Top
 
 
  Search
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this article
    Abstract
   Introduction
   Case Report
   Discussion
    References
    Article Figures

 Article Access Statistics
    Viewed1762    
    Printed40    
    Emailed0    
    PDF Downloaded190    
    Comments [Add]    
    Cited by others 3    

Recommend this journal