[Risks in diagnostic and therapeutic invasive cardiological procedures].

The risk of invasive cardiologic interventions being associated with morbid and mortal events is substantially related to the absolute numbers in whom these procedures are performed and this, in turn, is due to the epidemiologic significance of diseases of the cardiovascular system in industrialized countries. Diagnostic cardiac catheterization with coronary angiography is an invasive procedure with a relatively low risk of complications ( approximately 1%) or death (approximately 0.1%). Percutaneous transluminal coronary angioplasty (PTCA), on the other hand, carries a risk of complications of approximately 4% and has a mortality of approximately 1%. The major source of complications with intracoronary stent implantations relates to their thrombogenicity with acute or subacute closure of the vessel (rate of complications 6-15%, mortality approximately 2%). In vessels of < or = 3 mm in diameter, the restenosis rate of a stenotic lesion treated with a stent approximates that of conventional PTCA (one third). Patients with reduced left ventricular ejection fraction are at substantial risk if treated with drugs instead of bypass surgery (better long-term survival in the latter group.