Triglyceride deposit cardiomyovasculopathy (TGCV) is a novel disease concept we found in Japanese cardiac transplant candidates in 2008. Probands carried mutations in the PNPLA2 gene encoding adipose triglyceride lipase (ATGL). ATGL is the major enzyme that catalyzes the initial rate-limiting step of intracellular triglyceride hydrolysis to release free nonesterified long-chain fatty acids (LCFAs), which is an essential energy source for the normal heart. Patients with TGCV show ectopic accumulation of triglycerides in cardiomyocytes and smooth muscle cells resulting from abnormal intracellular metabolism of triglycerides and LCFA. TGCV is classified into primary and idiopathic TGCV with and without genetic ATGL deficiency, respectively. Both types of TGCV patients suffer from severe heart failure, arrhythmia, and coronary artery disease caused by lipotoxicity and energy failure at cellular levels. The Japan TGCV study group provided the diagnostic guideline and has been trying to develop a nutritional therapeutics with medium-chain fatty acids in order to overcome this intractable disease one day earlier. In this chapter, we describe clinical signs and symptoms, laboratory findings, diagnosis, and possible therapies of TGCV.
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This was partially supported by research grants for rare and intractable diseases from the Japan Agency of Medical Research and Development (AMED) (Grant No. 17ek0109092h0003) and from the Ministry of Health, Labour, and Welfare of Japan.
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