Biventricular Noncompaction Cardiomyopathy Accompanied by Severe Pulmonary Valvular Stenosis and Patent Foramen Ovale.

Myocardial non-compaction (NC) is a rare genetic cardiomyopathy commonly believed to develop an intrauterine arrest of endomyocardial morphogenesis. NC is characterized by markedly hypertrabeculations in left ventricle or both ventricles with deep intertrabecular recesses. NC is usually seen isolated, but sometimes other congenital heart abnormalities may accompany to the myocardial NC. In this article we have presented an adult patient with biventricular myocardial NC cardiomyopathy accompanied by severe valvular pulmonary stenosis and patent foramen ovale.

INTRODUCTION

Myocardial noncompaction (NC) is a rare congenital cardiomyopathy which is characterized by excessively prominent trabeculations of one ventricle or both ventricles with deep intertrabecular recesses.[1] NC is usually seen as isolated. However, some congenital heart abnormalities may accompany to NC.[2] In this case, we presented a 53-year-old female patient who had biventricular NC with severe pulmonary valvular stenosis and patent foramen ovale (PFO).

CASE REPORT

A 53-year-old female patient presented to our clinic with severe dyspnea and fatigue. Her medical history yielded nothing relevant. Her physical examination revealed central cyanosis, clubbing, and jugular venous distention. There were hepatojugular reflux and bibasilar crepitant rales in lungs. The peripheral pulses were palpable in all extremities. A normal S1, a widened split S2 with increased intensity, S3, and S4 sound was heard on cardiac auscultation. Furthermore, Grade 3/6 mid-systolic murmur was heard in the left upper sternal border.

A 12-lead electrocardiogram showed sinus rhythm with complete right bundle branch block. Her chest X-ray showed mild cardiomegaly and an increased bronchovascular branching. The N-terminal pro–B-type natriuretic peptide level was 10,900 pg/ml in routine laboratory tests and other results were normal. Arterial blood gas analysis revealed that pH was 7.39, PO2: 72 mmHg, PCO2: 29 mmHg, and SO2: 86%.

The transthoracic echocardiography (TTE) showed prominently increased wall thickness of both ventricles and hypertrabeculations in the apical and midventricular segments with deep intertrabecular recesses perfused from the Left ventricle (LV) and Right ventricle (RV) cavity. Typical double-layer structure was observed, and end-systolic ratio of the noncompacted to compacted myocardium was >2 [Figure 1a and b]. In addition, severe global LV systolic dysfunction with mild mitral and moderate tricuspid regurgitation was observed in TTE. Furthermore, continuous wave Doppler showed maximum 78.7 mmHg gradient at the level of the pulmonary valve which indicated severe pulmonary valve stenosis [Figure 1c]. Transesophageal echocardiography demonstrated PFO and atrial septal aneurysm.

Figure 1

(a and b) Transthoracic echocardiography images show significant increases in both ventricular wall thickness and prominent trabeculations ranging from apical regions to midventricular level with deep intertrabecular recesses. (c) Continuous wave Doppler shows maximum 78.7 mmHg gradient on pulmonary valve

Cardiac magnetic resonance imaging (CMRI) showed dilatation of the left atrium and right heart chambers with severe global systolic dysfunction of both ventricles. In CMRI, noncompacted-to-compacted myocardium ratio was 4.6 in apical and lateral segments of LV, total noncompacted LV myocardial mass index was 29 g/m2, and percentage of noncompacted LV myocardial mass was 48% with prominently increased trabeculations in many segments. Furthermore, RV noncompacted-to-compacted myocardium ratio was 3.7 [Figure 2a]. Hereby, diagnosis of biventricular NC was confirmed by CMRI. In addition, CMRI revealed severe pulmonary valvular stenosis and poststenotic dilatation [Figure 2b].

Figure 2

(a) In axial plane, T2 black blood image, the presence of significant trabeculations related to both ventricular cavities is observed. (b) In sagittal plane, balanced turbo field-echo image, pulmonary valvular stenosis and poststenotic dilatation are observed

After evaluation of echocardiography and CMRI, right and left heart catheterization was performed. NC was shown well in the ventriculography [Figure 3]. Percutaneous pulmonary balloon valvuloplasty was performed successfully and maximum gradient on pulmonary valve decreased to 25 mmHg. After pulmonary balloon valvuloplasty, symptoms and cyanosis markedly improved. The patient was discharged with optimal medical therapy and she is well now in follow-up.

Figure 3

Right ventriculography shows significant increases in the right ventricular wall thickness and prominent trabeculations ranging from apical regions to midventricular level with deep intertrabecular recesses

DISCUSSION

NC is a rare congenital cardiomyopathy commonly believed to be due to an arrest intrauterine of the endomyocardial morphogenesis.[1] NC was classified in the group of unclassified cardiomyopathies in the past, but nowadays, it is classified within genetic cardiomyopathies.[3] The first case with NC was defined in 1984 and NC seems with a frequency of 0.05%. However, with the development of multimodality imaging techniques, the reported incidence and prevalence of NC is significantly increasing in recent years.[4] Congenital heart abnormalities such as outflow tract obstruction, coronary artery abnormalities, atrial septal defect, and ventricular septal defect may accompany to the myocardial NC.[2] TTE should be preferred as initial method for diagnostic evaluation of NC and it is usually adequate for the diagnosis. Diagnostic criteria of NC in echocardiography are as follows: (i) at least three prominent trabeculations and presence of deep intertrabecular recesses; (ii) detection of blood flow within these recesses in the color Doppler examination; and (iii) demonstration of typical double-layer structure in diseased ventricular segment, and end-systolic ratio of noncompacted to compacted myocardium is to be >2.[5] Computed tomography (CT), CMRI, and ventriculography can be used alternatively in diagnostic workup of NC. The use of these techniques should be considered in patients who do not have adequate echocardiographic images and in patients whose diagnosis is not clear. Among them, CMRI is very valuable in the diagnostic workup in these patients. The Peterson and Grothoff's CMRI criteria have been defined for the diagnosis of LVNC.[67] The CMRI findings of our patients were satisfied the Peterson and Grothoff's diagnostic criteria of LVNC. LV is usual site of NC, but very rarely RV or both ventricles may be involved.[2] RVNC has been demonstrated only in a few cases of newborns with congenital heart defects and in adult patients. Therefore, there are no specific criteria for the diagnosis of RVNC. This is likely due to a small number of cases and less performed CT and CMRI for diagnosis in the past.

Symptoms usually develop due to systolic and diastolic dysfunction of LV in patients with NC. The Italian Registry of the Italian Society of Cardiovascular Echography has also demonstrated good prognosis in asymptomatic patients with preserved LV systolic function.[8] The patients with NC usually presents with symptoms of heart failure (HF), ventricular arrhythmias, or thromboembolic events. If HF develops in a patient with NC, the standard therapy of HF should be started immediately. Intracardiac defibrillator and cardiac resynchronization therapy should be considered in selected appropriate patients. Anticoagulation should be given to the patients who had thromboembolic events.[9] Heart transplantation may be considered in end-stage disease.[3] HF is a major cause of death in patients with NC. Ritter et al. showed that asymptomatic patients had a better prognosis than symptomatic ones in patients with isolated NC.[10] The patients who have HF symptoms, additional cardiac abnormalities, involvement of more than one ventricular segment, and the ratio of noncompacted to compacted myocardium >3 have poor prognosis.

CONCLUSION

NC is a rare congenital cardiomyopathy which has a poor prognosis. Therefore, early diagnosis of NC is very important for the disease management. The management of associated other cardiac pathologies will improve the symptoms and prognosis in patients with NC.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.