Cardio Flashcards
(19 cards)
Aortic regurgitation
Nocturnal palpitations and head pounding w exertion
- palpitations result from forceful ventricular contractions that eject large stroke volumes and head pounding can be due to unusually high amplitude pulsation of the intracranial arteries with each heart beat.
- involuntary head bobbing is a sign of widened pulse pressure
Nitric oxide
Most important mediator of coronary vascular dilation in large arteries and pre-arteriolar vessels. Synthesized from arginine and oxygen by endothelial cells and causes vascular smooth muscle relaxation
Maximal apical impulse
Can be felt at the 5th left intercostal space at the left mid clavicular line
Azygos veins
Lies in the posterior mediastinum immediately to the right of the midline and drain blood from the posterior intercostal veins into the superior vena cava
Mitral valve prolapse
PE: non-ejection mid systolic click followed by a late systolic murmur best heard that the cardiac apex
Traumatic aortic rupture
Most common site of injury is the aortic isthmus, which is tethered by the ligamentum arteriosum and is relatively fixed and immobile compared to the adjacent descending aorta
S3
- best heard with bell over apex with patient in left lateral decubitus position
- physiologic in young patients and well trained athletes
- in older individuals a sign of left ventricular failure
- heard during early diastole with the sudden deceleration of the entering blood column as the ventricle reaches its elastic limit (inability of the ventricle to accommodate blood flow)
- seen in mitral regurg and dialated ventricles
Alteplase
- fibrinolytic therapy for acute ST segment elevation MI
- converts plasminogen to plasmin and degrades thrombin and fibrin clots
- most common adverse effect is hemorrhage
Clopidogrel
Irreversibly blocks the P2Y component of ADP receptors on the platelet surface and prevents platelet aggregation. As effective as aspirin in the prevention of cardiovascular events in patients with coronary heart disease.
Dobutamine
Beta adrenergic agonist with predominant activity on B1 receptors. It causes an increased HR (+ chronotrope) and cardiac contractility (+ ionotrope), leading to an increased myocardial oxygen consumption.
Also, mild vasodilation.
Migratory thrombophlebitis
A paraneoplastic syndrome of hypercoagulability may be seen in some patients w cancer, esp adenocarcinomas of the pancreas, colon or lung. Adenocarcinomas produce thromboplastin like substance capable of causing coagulations that can disseminate and tend to migrate. Superficial venous thrombus that appear in one site and then resolve in another is known as Trousseau syndrome
Fracture of the pterion
Fracture of the skull where the frontal, parietal, temporal and sphenoid bones meet. Bone is thin in this region and there is risk of rupturing the middle meningeal artery and causing a epidural hematoma. Middle meningeal artery is a branch of the maxillary artery (one of the terminal branches of the external carotid artery)
Ultrastructual changes indicative of irreversible myocardial cell injury
Appearance of vacuoles and phospholipid containing amphorous densities within mitochondria generally signifies irreversible injury, and implies inability to generate ATP via oxidative phosphorylation. Simple mitochondrial swelling may be associated w reversible cell injury.
Intermittent claudication
Intermittent muscle pain reproducibly caused by exercise and relieved by rest defines claudication. Claudication is almost always a result of Athersclerosis in larger arteries. The obstruction is the result of fixed stenotic lesions produced by atheromas, lipid filled plaques that bulge into arterial lumen. Stenosis prevents sufficient blood flow during exercises resulting in ischemic muscle pain.
Substance P
Pain
Coronary steal phenomenon
Collateral microvessels form adjacent pathways for blood flow to areas distal to an occluded artery. Adenosine and dipyridamole are selective vasodilators of coronary vessels that can cause coronary steal, a phenomenon in which blood flow from ischemic areas is reduced due to arteriolar vasodilation in nonishemic areas –> hypo perfusion and worsening of existing ischemia
SA node
SA node acts as the dominant pacemaker site and is the site of earliest electrical activation. It is located at the junction of the right atrium and superior vena cava
AV node
Located in the right atrium near the septal cusp of the tricuspid valve
AV shunt
Abnormal communication btwn an artery and a vein that bypasses the arterioles, the major source of resistance in the vascular system. Can be congenital to acquired (penetrating injuries or dialysis access). PE may reveal pulsatile mass with a thrill on palpation. Auscultation reveals a constant bruit over the site. Increase preload by increasing the rate of blood return to the heart and decrease after load bc the arterioles are bypassed.
