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Background: Arrhythmogenic left ventricular cardiomyopathy (ALVC) is a left ventricle-dominant arrhythmogenic cardiomyopathy (ACM) subtype often associated with malignant ventricular arrhythmias, left ventricular (LV) scar and sudden cardiac death. Awareness about LV involvement is now on the rise. The diagnosis relies on structural abnormalities on cardiac magnetic resonance (CMR) imaging and known ACM-causing genetic mutations. Case summary: A 28-year-old lady (Case 1) was referred for cardiac screening after her father passed away suddenly. Her paternal uncle (Case 2) had been diagnosed with supposed dilated cardiomyopathy prior to referral. Both cases were worked up extensively with an electrocardiogram (ECG), 24-h ambulatory ECG monitor, exercise testing, and CMR imaging. Investigations of Case 1 showed T-wave inversion in the infero-lateral leads and a ventricular ectopic burden of 3% on ambulatory monitoring. Cardiac magnetic resonance imaging revealed moderately reduced LV systolic function (ejection fraction of 40%) with circumferential macroscopic fibrosis. Her uncle (Case 2) also had an impaired and dilated ventricle with extensive scar on CMR. Following the recent introduction of a cardiogenetic service in our unit, both were heterozygous for a pathogenic Filamin-C variant (c.7384+1G>A). Based on CMR findings and genetic results, the diagnosis of both patients was deemed to be ALVC. After years of surveillance, Patient 1 now has an implantable cardioverter defibrillator (ICD) indication. Discussion: The importance of diagnosing patients with ACM lies in the predisposition to sudden cardiac death. Gene-specific treatment algorithms in ACM may alter management strategies, including ICD implantation as primary prevention. An in-depth multidisciplinary discussion and respecting patient autonomy are key factors in any decision pertaining to ICD implantation.
RESUMO
Over the years, increasing evidence has shown that copy number variations (CNVs) play an important role in the pathogenesis and prognosis of Colorectal Cancer (CRC). Colorectal adenomas are highly prevalent lesions, but only 5% of these adenomas ever progress to carcinoma. This review summarizes the different CNVs associated with adenoma-carcinoma CRC progression and with CRC staging. Characterization of CNVs in circulating free-RNA and in blood-derived exosomes augers well with the potential of using such assays for patient management and early detection of metastasis. To overcome the limitations related to tissue biopsies and tumor heterogeneity, using CNVs to characterize tumor-derived materials in biofluids provides less invasive sampling methods and a sample that collectively represents multiple tumor sites in heterogeneous samples. Liquid biopsies provide a source of circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), tumor-derived exosomes (TDE), circulating free RNA, and non-coding RNA. This review provides an overview of the current diagnostic and predictive models from liquid biopsies.