Korean Circ J.  2017 May;47(3):413-417. 10.4070/kcj.2016.0302.

Cardiomyopathies with Mixed and Inapparent Morphological Features in Cardiac Troponin I3 Mutation

• Sohn DW
• Kim HK
• Kim YJ
• Oh S
• Seong MW
• Park SS

• KMID: 2385397
• DOI: http://doi.org/10.4070/kcj.2016.0302

Abstract

The fact that different types of cardiomyopathies can be manifested by the same sarcomere protein gene mutation in a single family is well known. However, mixed features of different types of cardiomyopathies in a single patient have not been well appreciated. We identified a novel mutation in cardiac troponin I3 (Arg186Gly) in the present case, and two of the family members showed mixed morphologic features of hypertrophic cardiomyopathy and left ventricular non-compaction. Moreover, both the features of cardiomyopathies were not apparent for each type of cardiomyopathy. In the patient's family, four other members had unexpected deaths before the age of 30.

Keyword

Hypertrophic cardiomyopathy; Left ventricular non-compaction; Restrictive cardiomyopathy; TNNI3

MeSH Terms

Cardiomyopathies*
Cardiomyopathy, Hypertrophic
Cardiomyopathy, Restrictive
Humans
Sarcomeres
Troponin*
Troponin

Figure

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  Fig. 1 Pedigree of the family described in this case report.

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  Fig. 2 Upper panel; initial echocardiogram in patient 2. (A) Absence of septal hypertrophy. (B) Only mild hypertrophy of the anterolateral wall was noted. (C) Prominent trabeculations were not noted at the apex. Lower panel; follow up echocardiogram done 9 years after the initial echocardiogram. (D) Prominent whole septal hypertrophy was noted, in addition to the increased anterolateral wall hypertrophy. (E) Apical 4 chamber view shows a couple of prominent trabeculations and deep recesses (arrows).

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  Fig. 3 Initial echocardiogram of patient 3. (A, B) Asymmetric hypertrophy was not as obvious as the typical case of hypertrophic cardiomyopathy. Both hypertrophied and normal segments are indicated as arrowheads in each figure.

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  Fig. 4 Echocardiogram in patient 3 at the time of admission to neurology department due to stroke. Although dominant rhythm during the admission was atrial fibrillation, sinus rhythm was occasionally noted and even in the sinus rhythm, patient showed restrictive physiology. (A) Apical 4 chamber view showing marked left atrial enlargement. (B, C) Mitral inflow and mitral annulus velocity profiles.

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  Fig. 5 Echocardiographic findings in patient 4. (A) Only localized area of hypertrophy at the basal anterolateral wall (arrowheads) was noted, (B) Mitral annulus velocity profile. Early diastolic mitral annulus velocity (7 cm/sec) was low for the patient's age, indicating presence of relaxation abnormality. (C) Apical 4 chamber view. Prominent trabeculations were noted (arrows). (D) Mitral inflow pattern. Normal looking mitral inflow; however, considering the relaxation abnormality indicated by the mitral annulus velocity profile, this mitral inflow pattern is regarded as a pseudo-normal filling pattern.

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