Case scenario: A.O. is a 70-year-old woman with a 5 year history of congestive h
ID: 3505437 • Letter: C
Question
Case scenario: A.O. is a 70-year-old woman with a 5 year history of congestive heart failure (CHF) secondary to a large left ventricular infarct. She has had increasingly poor activity tolerance and now requires assistance with activities of daily living. Even minimal activity is associated with moderately severe dyspnea and exertional chest pain, which is relieved by rest. A.O. has also recently exhibited marked pedal edema bilaterally. She takes digitalis, furosemide (Lasix) and sublingual nitroglycerin. She is currently hospitalized for evaluation and management of worsening in her CHF. Which type of heart failure (left or right sided) is usually associated with the clinical manifestation of dyspnea and what other clinical findings are likely to be present with this type of heart failure and what is the mechanism behind their development?
Explanation / Answer
Ans: The type of heart failure she's suffering from is LEFT SIDE Congestive heart failure. We come to know as it's developed secondary to left ventricular infarct . Reason for CHF after infarct is that due to infarct ( damaged heart tissue) the left ventricle isn't pumping blood enough for body needs so the tissues which require consistent blood flow due to reduced blood flow are shortening of oxygen in other words its called HYPOXIA.
So due to Hypoxia of brain the respiratory center in the medulla is triggered to cause hyperventilation. So only the person breathes faster and faster trying to catch his / her breath this is called DYSPNEA ( difficulty in breathing) .
Clinical findings : dyspnea causes low o2 content of blood, High co2 content ( both can be analysed by doing blood gas analysis) , her haemoglobin levels would increase ( so as to carry more oxygen) , High PCV ( more RBCs) , the person is always fatigued and weak, any exertion causes dyspnea , chest pain . ( This are most common easily identifiable findings)
Mechanism: When heart is pumping blood which isn't enough to meet the requirement of the body tissues the body finds ways to deal with it like increses RBC production so more haemoglobin is available to carry some more amount of o2 in the less amount of blood , now since the tissue blood supply is less and the person does something like exercises or running it'll cause lactic acid accumulation which won't be cleared off by the blood easily and lead to cramps and fatigue . Chest pain is due to reduced blood flow to the heart itself by the coronary circulation ( it's called angina) . The blood obviously is not effectively pumped due to damaged heart tissue so it's left , in the left ventricle this causes cardiomegaly ( increase in heart size) compressing the structures around it like trachea, oesophagus etc.