PCCN Master Questions and Answers

How does chronic aortic stenosis lead to left ventricular hypertrophy? Chronic aortic stenosis leads to left ventricular hypertrophy bc of increased workload of pumping blood through a narrow opening. The left atrium can also enlarge but mainly causes left ventricular hypertrophy. The right ventricle will remain normal for a period of time. That's why LHF happens first then leads to RHF. Chronic mitral stenosis will cause enlargement in which area? Left atria hypertrophy. In pt with Mitral valve stenosis, their valve thickens, reducing blood flow from left ventricle to left atria. The pressure in left atria becomes high, causing enlargement overtime, then pt will be at risk for a fib bc the left atria becomes so thick than it cannot properly contract and just quivers so higher risk for blood ctot bc the blood isn't moving. Pt with left atria hypertrophy are at risk for... A fib Left atria becomes so thick that it cannot properly contract and just quivers so higher risk for blood clot bc blood isn't moving What is the most common cause of mitral valve stenosis? Rheumatic fever which causes inflammation of the valves Pt with hypertrophic cardiomyopathy should be on what med? Beta-blocker like Metoprolol (Lopressor) and Calcium Channel blockers In hypertrophic cardiomyopathy, the heart becomes so thick that it cannot pump effectively so pt needs beta-blocker or CCB to slow down the heart rate to maximize diastolic filling time in a reduced left ventricle Pt with dilated cardiomyopathy should be on what med? FIRST give meds that reduce afterloadTHEN escalate to inotropic drugs like Digoxin In dilated cardiomyopathy the heart becomes weak and can't pump as hard so you need a positive inotropic med like digoxin to help heart pump harder Pts with dilated cardiomyopathy will have what symptoms? Ventricular dysrhythmias d/t poor contractility. Dilated cardiomyopathy --> poor contractility --> ventricular dilation and increase in blood volume --> mitral valve regurgitaton. ***Cardiogenic shock will cause... High or low preload? High or low afterload? High preload bc heart can't pump High afterload because the blood vessels vasoconstricts as a compensation mechanism for decreased stroke volume aka perfusion. What are sx of cardiogenic shock? JVD (back up of blood) Hypotension Tachycardia (compensation mechanism) Pt has these symptoms: hypotension, narrowing pulse pressure, thready pulse, and tachypnea What do they have? Cardiac tamponade Wide mediastinum on chest x-ray: aka large accumulation of blood Narrow pulse pressure: low SBP (not pumping) but high DBP (vasoconstriction) Hypotension: heart not pumping blood out to body Cardiac Tamponade: - Definition - Sx - Tx Definition: when heart is compressed by blood or fluid in pericardial space so it cannot relax and fill during diastole. Cannot pump!!! Too much pressure! Sx: hypotension (compressed heart not pumping), JVD (back up of blood), narrow pulse pressure (bad), Pt will have "muffled heart sounds", and "distant heart tones" Tx: emergency pericardiocentesis Beck's triad is a combination of symptoms useful in diagnosing cardiac tamponade. They are? Distended neck veins Muffled heart sounds Hypotension Tachycardia is an early sign of tamponade. A narrowed pulse pressure occurs, and fluid cannot be ejected from the heart. The muffled heart sounds occur because the fluid in the sac minimized the transmission of sound waves. Which of the following hemodynamic changes will occur with cardiac tamponade? • Increased cardiac output • Stroke volume decrease • Contractility increases • Decreased heart rate STROKE VOLUME DECREASE Because the heart cannot adequately fill or eject its contents, stroke volume (SV) decreases and causes a decreased cardiac output (CO). Contractility decreases because the muscles cannot stretch and, therefore, cannot contract effectively.