Since the first treatment of a patient with severe stenosis of the left anterior descending coronary artery using the percutaneous balloon angioplasty technique, pioneered by Andreas Gruentzig more than 25 years ago, the thriving subspeciality of lesser-invasive transcatheter therapeutics has become an important treatment alternative in patients with cardiovascular disease (CVD). Although balloon angioplasty has been supplanted by, first, bare metal stents (BMS) and, most recently, drug-eluting stents (DES) as the mainstay therapy in patients with coronary vascular disease, the original device development principles espoused by Gruentzig have impacted the current generation of innovative transcatheter devices. These principles include design simplicity, a focus on unmet clinical needs, a reliance on evidence-based medicine and clinical research, and an emphasis on patient safety, predictability, generalisabilty and efficacy.
Importantly, the initial emphasis on coronary vascular disease has extended to endovascular therapies in extracoronary vascular disease and structural heart disease, which includes adult congenital lesions and valvular heart disease. Endovascular transcatheter therapies now address symptomatic patients with peripheral vascular disease, renovascular lesions, neurovascular disease (especially bifurcation carotid stenoses) and aortic disease (abdominal and thoracic endografts). Over the past few years there has been an explosive interest in nonvascular structural heart disease. This new evolving treatment opportunity embraces a wide diversity of disorders ranging from patent foramen ovale closure to transcatheter aortic valve replacement and requires different physician skill sets, such as an advanced knowledge of echocardiographic modalities.
The remarkable progress in the aforementioned non-surgical catheter-based treatments for cardiovascular disease has importantly influenced patient care strategies and sub-speciality physician training programmes. Non-surgical transcatheter devices can provide definitive treatments for frequently encountered morbid illnesses such as acute ST-segment elevation myocardial infarction (MI) and can provide safer alternatives in patients with multiple co-morbid conditions. Future interventional physician therapists will require multidisciplinary expertise in areas as diverse as biomedical engineering, pharmacokinetics and vascular biology. Moreover, the assessment of new therapies via appropriate clinical trials necessitates a commitment to understanding esoteric principles of clinical trial design and analysis.
In the future, we anticipate further advancements in response to pressing clinical imperatives. Advanced generations of DES must improve safety by eliminating the risks and consequences of late stent thrombosis. Methods to reduce myocardial necrosis after acute MI and to identify so-called vulnerable or rupture-prone plaques are under active investigation. Prominent among such therapies is the exciting field of stem cell therapies, which have the potential to facilitate angiogenesis and/or myogenesis. Lastly, rapidly improving cardiovascular imaging techniques, such as computer-assisted tomographic (CAT) angiography, will enhance and simplify diagnoses and help to guide resultant therapies. There is no sub-speciality in medicine over the past quarter of a century that has enjoyed a steeper growth trajectory than interventional cardiovascular therapeutics and it promises to offer future innovative treatment possibilities to solve important clinical problems.