In the pre-genomic era, the opportunity to identify a relevant set of causative genes for multigenic diseases such as atherosclerosis and cardiomyopathies was limited. Traditional genetic approaches were designed to find single loci or genes with the power to cause Mendelian cardiovascular disorders such as the prototypical familial hypercholesterolemia. The obvious critical challenge is to identify the genes that collectively contribute to multigenic disorders such as cardiovascular deseases (CVD). The precise combination of environmental and genetic factors responsible for these disorders may vary between patients, producing phenotypically similar manifestations but requiring different interventions to correct them. It is important that an accurate and expeditious diagnostic system must be available to help physicians make a rapid diagnosis. More detailed characterization of pathological processes at the molecular and cellular levels will enhance understanding of underlying mechanisms and will be provided unequivocal diagnosis beneficial for appropriate drug therapy and genetic counseling. Rapid advances in molecular biology in the past decade have contributed to the development of molecular cardiology and providing new diagnostic and therapeutic tools. Basic technologies of molecular diagnostics are the Southern blot, DNA samples, pulsed field gel electrophoresis, and polymerase chain reaction (PCR). PCR is a method of nucleic acid analysis specific test with applications in diagnosis of various diseases, including cardiovascular deseases. PCR has revolutionized molecular diagnostics. New methodologies have offered the opportunity to analyze and in some cases to quantify simultaneously, thousands of messenger RNA transcripts. This type of analysis has been termed gene expression profiling. Medical researchers are now using expression profiling to systematically characterize molecular events pertaining to complex multifactorial diseases. Serial analysis of gene expression, differential display, subtraction suppression hybridization, and DNA microarrays are four major methods used for expression profiling. Microarray analysis can generate novel hypotheses relating to the cardiovascular pathologies, and further studies with animal models, molecular biology, cell biology and biochemistry will validate these hypotheses and will eventually generate novel diagnostic and therapeutic markers, and identify potential drug targets which will serve to bring about more effective management of cardiovascular disease. It will facilitate the point-of-care diagnosis of genetic cardiovascular disorders and enable the development of personalized cardiology. Biotechnology is also making important contributions to cardiovascular diagnostics. The advent of highly reliable and efficient techniques in recombinant DNA has enabled the identification of many genes causative of CVD. In molecular diagnostics are used biosensors that are based on antibodies, enzymes, ion channels, or nucleic acids. Biosensors incorporate a biological sensing element that converts a biological event into an electrical signal that can be processed. A biosensor’s biological component provides specificity, the ability to selectively recognize one type event. Its transducer confers sensitivity, the ability to transform the very low energy of the biological event into a measurable signal. These advances will allow us to understand the gene regulation of cardiac and vascular growth, to identify genes responsible for cardiovascular diseases, to perform diagnostic in situ hybridization and develop gene therapy approaches to cardiovascular diseases. This implies the urgent need for future cardiovascular research.