Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages and manifests in adults with a suspicion of typical ECG changes of giant T wave inversion in left precordial leads. Transthoracic echocardiography is the mainstay of non-invasive diagnosis and provides a heterogeneous appearance of its morphological features with a spade-shaped LV (left ventricular) cavity. Background of this case study describes the apical HCM in an asymptomatic male at the age of 54 years old and also predicts the mixed and mid-ventricular forms of left ventricular HCM at this region of Thoothukudi in India.
Apical hypertrophic cardiomyopathy (apical HCM) is an atypical phenotype of non- obstructive HCM (hypertrophic cardiomyopathy) and it is more prevalent in Japanese people [
Apical HCM was first described in Japan. Sakamoto et al. first described the ECG pattern of apical HCM in 1976 [
Published Indian studies are limited for comparison, so this case had been reported.
A 54-year-old asymptomatic male was referred for echocardiographic evaluation due to an LVH (left ventricular hypertrophy) pattern of ECG changes as shown in
Hypertrophic cardiomyopathy (HCM) is the most common genetically transmitted cardiovascular disease and it is usually familial with heterogeneous expression. Several disease-causing mutations in genes encoding proteins of the sarcomere have been reported [
Left ventricular hypertrophy is a gross anatomic marker and major determinant of the clinical feature of the disease [
trophy in unusual locations such as the posterior portion of the septum, the postero- basal free wall and the mid-ventricular level [
Embryologically, asymmetric septal hypertrophy results from postnatal persistence of a normal anatomic feature of the developing heart [
According to the distribution of hypertrophied musculature, the morphologic sub classification as “true apical” phenotype (hypertrophy of only the apical segment below the papillary muscle) and “distal-dominant” phenotype (hypertrophy extended into the middle LV segments) have been recently recognized in North America [
ovascular events. Other investigators have separated the AHCM into “pure form” (apical segment only) and “mixed form” (hypertrophy extending into other segments) [
A relatively normal-sized, diffusely hypokinetic left ventricle with an unexplained, pathological hypertrophy is termed as “burned-out” hypertrophic cardiomyopathy.
Clinical expression of apical HCM is highly variable. Apical HCM may manifest early in adulthood [
Apical hypokinesis and aneurysm formation may also result from midventricular (mid-cavity) obstructive type of hypertrophic cardiomyopathy and transient LV (left ventricular) apical ballooning, a characteristic feature of Takotsubo cardiomyopathy (stress cardiomyopathy or apical ballooning syndrome or broken-heart syndrome) which was originally described in Japan in 1990 and it is most commonly seen in elderly post-menopausal women, characterized by ST segment elevation in anterior precordial leads with elevated cardiac enzymes and may be due to excess catecholamines (diffuse microvascular spasm or dysfunction, resulting myocardial stunning or direct myocardial toxicity), coronary vasospasm and triggered by emotional or physical stress. It may presents with sudden onset of chest discomfort, shortness of breath and reversible within weeks to months. A criteria formulated by Mayo clinic as regional hypokineses with ECG evidence of ST-segment elevation in the absence of obstructive coronary artery disease, pheochromocytoma or myocarditis to diagnose this condition. During the event, the shape of LV cavity resembles the fishing pot of Japanese (Tako-tsubo) to trap octopuses and so it is called as Takotsubo cardiomyopathy. The typical form of this cardiomyopathy is apical type, characterized by systolic apical ballooning with hypokineses of apical and mid segments and hyperkineses of basal walls. The atypical variants such as mid-ventricular type (hypokineses restricted to mid-ventricle with sparing of apex), basal type (hypokineses of base with sparing of mid-ventricle and apex), focal type (dysfunction of a segment, usually anterolateral) and global type (global hypokineses) were also described.
The most common ECG findings are negative T waves in the precordial leads, found in 93% of patients (a depth >10 mm in 47%) and a documented left ventricular hypertrophy on imaging is seen in 65% of patients with HCM. Giant T wave negativity (defined as depth or voltage >1 mV or 1.2 mV in any of the leads) in the left precordial leads is the hallmark feature of apical HCM as a result of balance of electrical forces emanating from the left versus the right ventricle [
Altered repolarization changes of ventricular myocardium may produce ST segment/ T wave changes in 70% of cases of left ventricular hypertrophy. There is significant variability on manifestation of strain pattern as minimally inverted or >5 mm depth, asymmetric T waves with rapid return to baseline and terminal positivity, depression of the J point, T wave inversion in lead V6 > 3 mm and greater in V6 than V4 [
In apical HCM, larger degree of T wave inversions are seen and it’s depth does not correlate with severity of apical hypertrophy [
Abnormal ECG changes and no echocardiographic evidence of hypertrophic cadiomyopathy is seen in some patients due to abnormal gene in first degree relatives and called as carrier or preclinical state of hypertrophic cardiomyopathy. Incidence of deep T inversion may diminish considerably with advancing age. Myocardial infarction with a secondary apical LV aneurysm may occur in 10% of cases, that might determine the disappearance of the giant T waves in apical HCM and the “spade” shaped LV configuration may become “bottle-gourd “shaped. In normal variant of hypertrophic cardiomyopathy (HCM), the LV (left ventricular) cavity is usually “banana” shaped. However, in some cases, non-giant T waves may become a giant one on later life. The T wave changes associated with ischemia are usually narrow and symmetric (deep T wave inversion) and “CVA (cerebrovascular accident)-T wave pattern” is associated with marked QT prolongation especially in subarachnoid hemorrhage.
The preferred initial imaging test is Transthoracic Echocardiography and it is the most frequently utilized diagnostic modality [
Relative hypertrophy was defined as the absence of hypertrophy (wall thickness <14 mm) but with the apical wall thickness greater than the basal thickness (apex:base ratio (ABR) wall thickness >1). An apical- to-basal LV wall thickness ratio of 1.3 - 1.5 is diagnostic of apical HCM [
Apical HCM is characterized as concentric, circumferential hypertrophy of the entire apex due to apical left ventricular thickening of the anterior and posterior walls, resulting in a spade-like morphology of the left ventricular cavity during end diastole in LV long axis view of MRI and RAO projection of angiography. A subtype of apical HCM in which the distribution of hypertrophied myocardium proved to be confined to the apical lateral wall (AAH-asymmetric apical hypertrophy) and cannot be evaluated in long axis MRI or RAO projection in angiography and this subtype was called as non- spade apical HCM in short axis images of MRI [
A criteria was formulated to diagnose apical HCM in a distinct phenotype [
1) -Two essential criteria
-Deep ECG T wave inversion
-Relative apical hypertrophy (ABR > 1)
2) -Four minor or supportive criteria
-Myocardial scarring by LGE CMR (late gadolinium enhancement cardiac magnetic resonance)
-Presence of apical aneurysm or microaneurysm
-Left atrial dilatation
-Apical cavity obliteration >20 mm
The presence of two or more of four minor criteria is the supportive evidence of apical HCM. The differential features of Japanese and non-Japanese type of apical HCM is shown in the
In transthoracic echocardiography, the lateral wall hypertrophy is more than the
Japanese Type
Non-Japanese Type
Mostly seen in males
Elderly female in Asians and younger in West
“Pure” form is predominant
“Mixed” form is predominant
Asymptomatic and benign
Complications may occur
T-wave negativity is more pronounced
Less pronounced
Increased hypertrophy confined to apex
Segmental distribution may occur. Basal septal hypertrophy producing sub aortic obstruction in 50%, mid-septal hypertrophy with mid-cavity obstruction in 25%, apical septal hypertrophy with apical obliteration in 25% of cases. Occasionally, papillary muscle hypertrophy alone may be seen
Apical wall thickness lesser degree
More than Japanese in Americans
apical septum and producing a classical “ace of spades sign” in apical four chamber [
apical 4 chamber view of this patient in end-diastolic image. The anterior mitral leaflet is long and elongated and mildly regurgitant as shown in
Lateral wall thickening was smooth, homogeneous, non-trabeculated in apical HCM and thus differentiated from non-compacted LV (left ventricular) cardiomyopathy and apical HCM may mimic as apical LV thrombus which may be associated with wall motion abnormality. It can also mimic LV EMF (Endomyocardial fibrosis), but EMF is characterized with firm, rolled edges and a rugose surface over the endocardium.
Apical HCM is generally associated with good prognosis in both Asian and Caucasian population and a long-term mortality is 0.1% per year. The approach to management of apical HCM depends on symptoms and risk of sudden cardiac death (SCD). There is lesser incidence of sudden cardiac death in apical variant, compared to patients with normal variant HCM.
In asymptomatic patients, no specific therapy has been outlined, but counseling is certainly recommended for symptomatic monitoring to notice any syncope or presyncopal events on follow up. The medical regimen in symptomatic patients primarily consists of beta-blockers, which have been shown to decrease symptoms as well as overall mortality [
The major clinical features associated with increased risk of SCD in HCM patients are non-sustained ventricular tachycardia, maximum LV wall thickness of ≥3 cm, family history of SCD at younger age, unexplained syncope, abnormal BP response during exercise and increased left atrial diameter (>36 mm) as a potential SCD risk modifier. Current guidelines do not recommend ICD (implantable cardioverter defibrillator) implantation as a primary prevention for SCD in apical HCM and these clinical features should be used to assess the prognosis on follow up.
In apical HCM complicated with apical aneurysm formation, the size and symptoms of the aneurysm were ameliorated by sub selective coronary angiography and alcohol injection into the small vessels supplying a limited segment of mid-LV obstructive muscle. Others have reported the use of surgical apical myectomy in similar circumstances [
An increased apical thickness of 55.3 mm indicate massive hypertrophy (>50 mm [
Echocardiographic screening of population was done in those individuals having ECG changes of LVH (left ventricular hypertrophy). A mixed form of apical HCM (with involvement of IVS) was found in a 65-year-old asymptomatic hypertensive female as shown in
A 60-year-old hypertensive woman having a mid-ventricular obstructive form of HCM with LVH (left ventricular hypertrophy) ECG pattern was observed and the gradient of obstruction may mimic apical dyskinesis with aneurysm as shown in Figures 18-22. The woman developed sudden onset of angina with an elevation in blood pressure up to 160/90 mmHg and cardiac enzymes (CK-MB fraction rises to 125 IU/L- normal < 25 IU/L). The ECG during the event showed LVH (left ventricular hypertrophy) pattern with VPCs (ventricular premature complexes) as shown in
form of HCM (hypertrophic cardiomyopathy) is frequently observed in elderly hyperensives with LVH (left ventricular) pattern of ECG changes and more prone to complications such as ischemia and infarction.
Genetic screening may be done in younger population if there is a family history of sudden death since hypertrophic cardiomyopathy (HCM) is the most common cause of
death in competitive athletes [
individuals without outflow tract obstruction. The exact molecular pathogenesis of HCM is to be determined and so the definite therapy based on gene manipulation remains speculative.
The initial echocardiographic evaluation was sufficient to diagnose the patients with apical HCM [
Sokolow-Lyon index. The diagnosis of apical hypertrophic cardiomyopathy was primarily made from ECG changes and specific morphologic criteria as assessed non-in- vasively by Transthoracic echocardiography. The condition should be considered when encountering a 12-lead ECG showing giant T-wave inversion [
ventricular) cavity in all views of echocardiographic imaging was recognized and it remained aymptomatic in this 54-year-old male at this belt of Thoothu- kudi in India. The mixed and mid-cavity forms were detected in this region with a relatively benign and late onset disease in adult life. Mid-ventricular obstructive form with an anginal episode was also reported in an elderly hypertensive female at the age of 60 years old.
Muthiah, R. (2016) Apical Left Ventricular Hypertrophic Cardiomyopathy: A Case Report. Case Reports in Clinical Medicine, 5, 308-329. http://dx.doi.org/10.4236/crcm.2016.59049