Patent ductus arteriosus in dogs.

Patent ductus arteriosus (PDA) is the most common congenital heart disease in dogs. It is due to the failure of the ductus arteriosus muscle to constrict, leaving a passageway for blood flow and resulting in eventual left-sided heart disease and/or generalized heart failure. It is hereditary in several breeds. The typical left-to-right PDA is amenable to minimally invasive procedures or open surgery. The ideal surgical candidate for PDA occlusion is immature and lightweight, with minimal heart changes. There is a wide variety of surgical techniques involving different methods of dissection and suture passage. Intraoperative hemorrhage during dissection is the most serious potential complication and can be life-threatening. Minimally invasive techniques such as thorascopic ligation and intravascular coiling have been claimed to have lower morbidity and mortality than open techniques. Once the PDA is occluded, most patients have remodeling of the myocardial tissues, resulting in an excellent long-term prognosis. Late complications such as residual flow and recanalization are rare but may be clinically significant.