Vasospastic

Vasospastic is an adjective describing conditions or processes characterized by vasospasm, a transient constriction of the muscular wall of a blood vessel that reduces or blocks blood flow. Vasospasm can affect arteries supplying the brain, heart, extremities, or other tissues, and the term is commonly applied to cerebral vasospasm after subarachnoid hemorrhage, vasospastic (Prinzmetal) angina, and Raynaud phenomenon.

Causes and mechanisms: Vasospasm results from abnormal reactivity of vascular smooth muscle and endothelial dysfunction. Mediators such as endothelin-1, reduced nitric oxide availability, and calcium influx promote sustained constriction. Triggers include cold exposure, stress, smoking, and certain drugs or toxins.

Clinical features: Cerebral vasospasm may present with new focal neurological deficits or decreased consciousness several days after hemorrhage. Coronary vasospasm causes chest pain at rest with transient ischemic changes. Raynaud phenomenon manifests as episodic color changes, numbness, and discomfort in the fingers or toes, often in response to cold or stress.

Diagnosis: Diagnosis relies on clinical presentation and imaging. Transcranial Doppler ultrasonography detects increased flow velocity in affected vessels; CT or MR angiography visualizes arterial narrowing; coronary angiography assesses coronary vasospasm. Provocative testing may be used in research settings.

Management: Treatment emphasizes avoiding triggers and promoting vasodilation. First-line therapy typically includes calcium channel blockers; nitrates may relieve acute episodes. Nimodipine is specifically recommended to reduce delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage. In refractory cerebral vasospasm, endovascular therapy with intra-arterial vasodilators or angioplasty can be considered. For Raynaud phenomenon, protective measures and vasodilator therapy are used as appropriate.

Prognosis: Outcomes depend on the underlying condition and timeliness of treatment; cerebral vasospasm after subarachnoid hemorrhage can lead to significant morbidity if not promptly managed.