Factors determining heterogeneity in coronary collateral development: A clinical perspective.

The mechanisms responsible for collateral development have attracted considerable attention in cellular and molecular research because these vessels have the capacity to protect against myocardial infarction and reduce exercise-induced ischemia. This has led to a number of phase I trials employing angiogenic peptides, genes and cell transplantation. However, there are significant differences in the degree of collateral development among patients even with similar patterns of coronary disease. Understanding the factors responsible for this heterogeneity has important implications for the efficacy of future therapeutic strategies. Therefore, this review will examine these factors from the clinical perspective integrating the clinical evidence with recent molecular and cellular studies. The role of specific pharmacological agents and novel investigational strategies will be discussed.