Left ventricular hypertrabeculation/noncompaction in β‐thalassemia

Abstract

Left ventricular hypertrabeculation/noncompaction in b-thalassemiaWith interest we read the article by Piga et al. about the prevalence and risk factors of left ventricular hypertrabeculation (LVHT) in patients with b-thalassemia presenting for iron assessment by cardiac MRI [1]. We have the following comments and concerns.Interestingly, the authors excluded patients with b-thalassemia and a neuromuscular disorder (NMD). It would be interesting to know how many patients were excluded because they presented with a NMD and which NMDs were diagnosed. How many patients were investigated by a neurologist familiar with NMD? How many underwent instrumental investigations to confirm or exclude a NMD? Did any of the included or excluded patients undergo muscle biopsy? Previous studies found that up to one-third of the adult patients with thalassemia major present with muscle weakness, wasting, and muscle cramps but usually normal CK and aldolase values [2]. NMD was also found in 28% of the pediatric patients with thalassemia [3]. Myopathy in b-thalassemia may be due to intra-mitochondrial iron accumulation [4]. Patients with thalassemia and myopathy should not be excluded from the study.LVHT occurs familiarly [5]. In how many of the 18 patients with LVHT were other family members screened for LVHT? How many other family members presented with LVHT and thalassemia? Did the mother of the one patient with LVHT also present with thalassemia? In case she did not have thalassemia, which other disease was underlying LVHT? Familial LVHT may not predominantly follow an autosomal dominant trait of inheritance. Also autosomal recessive, X-linked or maternal transmission has been reported [6].The authors speculate that LVHT in thalassemia is acquired [1]. They assume that LVHT is the consequence of a remodeling process triggered by anemia or hypoxia. However, there are no indications that patients with LVHT more frequently present with anemia than patients without LVHT. If they assume that LVHT had developed during life, it is essential to review previous echocardiographic or cardiac MRI investigations to see if LVHT was truly absent before its first detection. How many of the 18 patients with LVHT had undergone previous imaging investigations of the left ventricular myocardium? In how many was LVHT absent and thus acquired?