Therapeutic ultrasound in cardiology.

Ultrasound can be exploited to derive therapeutic results by using its bioeffects such as creation of mechanical vibrations, localized cavitations, microstream formation, physicochemical changes and thermal energy. Extensive in vitro and animal investigations during the last 2 decades have laid a foundation for ultrasound energy to be used for treatment purposes in various medical specialties. In the area of cardiovascular diseases, ultrasound could be used for thrombolysis, adjunct to coronary interventions, drug delivery, local gene transfer, and creating therapeutic lesions. The dispensation approaches to therapeutic ultrasound are varied, from the use of low- to medium-range frequency, low to focused high intensity, and catheter-based to external devices. Catheter-based ultrasound could be useful for intracoronary thrombolysis, and external ultrasound instrument with transcutaneous delivery could be of use in applications such as creation of myocardial lesions, peripheral vessel thrombolysis, and drug and gene delivery. Adjunct administration of microbubbles has been found to enhance thrombolysis, and drug and gene therapy. Ongoing studies strongly suggest that therapeutic ultrasound could have an important role in cardiovascular disorders associated with thrombosis, inflammation, atherosclerotic disease, and arrhythmias.