CLINICAL PATHOPHISIOLOGY 1
Pathophysiology of Congestive Heart Failure
CHF refers to a disorder in which the heart fails supply sufficientblood to aid in metabolism. The major causes of this incident arealterations in the mechanical functioning of the heart. Thesemechanical functions are systolic and diastolic by the ventricle.This can happen if the patient has other health complications or not.In the former, the heart fails due to structural defects. In thelatter, the heart fails to respond adequately to an unexpectedincrease in the volume of blood that it is required to pump.Hollenberg & Heitner (2012) say that congestive heart failure isnot a disease, rather a clinical syndrome facilitated by blood volumesurge, failure of the heart muscles to perform adequately and thelack of vigor tolerance. Regardless of the cause of the condition,hypoperfusion of the heart muscles is caused by the lack of normalpumping, after which the heart suffers a series of systemiccongestion, leading to the actual failure.
Asa syndrome, the condition results due to an irregularity in thestructure, working and tempo of the heart (Figueroa & Peters,2006). Patients from developed countries are mostly diagnosed withventricular dysfunction, which is a result of myocardial infarctionand hypertension. The most vulnerable demographic are the elderly,who are most likely to have suffered from comorbid conditions.However, in some cases, renal dysfunctions and depression are listedamong the significant risk factors. Besides being an indication ofthe failure of the heart to supply the body with enough oxygen,congestive heart failure is also a strong indication of systemicresponse the inadequacy. While determining the pathophysiology ofcongestive heart failure, Hollenberg & Heitner (2012) note twomain variables. These are the preload and the afterload. These twohelp cardiologists to determent the pathophysiologic consequences ofthe condition and the possible treatment approaches that they can useon patients.
Clinicalassessments help to express the preload as the blood capacity of theleft ventricle. Notwithstanding the major role it plays indetermining the function in of the heart muscles, preload does notdepend on the intravascular volume only. Hollenberg & Heitner (2012) say that any impediments predispose preload to the ventricularfilling. The right atrial pressure of the heart is most likely to bereduced by an increased pleural pressure. This is because the heartis located in the thoracic cavity. When this happens, the ventriclefilling may be significantly affected. As a response, the cardiacpump will adjust the pumping pressure, with the objective ofresponding to the output volume. As described by Frank-Starling law,an increase in the volume of the pump will lead to a normalphysiologic state (Figueroa & Peters, 2006). However, when thedetermined plateau is not reached, there are most likely to becomplications that may lead to the condition.
The diastolic function, a concept key to understanding congestiveheart failure, is determined by a set of factors (Figueroa &Peters, 2006). The first one is the dispensability of the leftventricle. This defines the process of relaxation, which is key tometabolic energy. When the normal ventricular dispensability isaffected by a changed structure, the preload is impaired. Theimpairing is evident in during the diastolic dysfunction. The secondfactor is cardiac contractility. This is the way that the heartmuscles pump blood. The heart responds to the preload as influencedby stroke volumes. Non-functioning of the myocardium impairscontractility, which is a key factor in congestive heart failure.
Figueroa, M, S. & Peters, J.I.(2006). Congestive heart failure: Diagnosis, pathophysiology,therapy, and implications for respiratory care. RespiratoryCare, 51(4): 403-412.
Hollenberg, S., & Heitner, S.(2012). CongestiveHeart Failure (pp.91-111). Humana Press.