Clinical Vignette, Acute Heart Failure Syndromes - Essay Example

?Clinical Vignette After establishing diagnosis of acute anterior septal myocardial infarction, a 68 year old woman was treated by implantation of a single metal stent in the appropriate coronary blood vessel. Following the procedure she underwent 5 days of hospitalization after which she was considered fit enough to be discharged. Medications prescribed at the time of discharge were oral clopidgrel, aspirin, metoprolol, perindopril and atorvastatin as she had past history of hypertension coupled with diabetes type II. The woman had a body mass index of 35 which is considered as obese according to NIH (National Institute of Health, United States) (NIH Website). The drugs prescribed demonstrate that the endeavor was to keep her blood pressure within normal limits, to keep her cholesterol levels in check and prevent any further cardiovascular complications, primarily as a measure to reduce the risk of a heart attack (NIH). The prescribed drugs are standard regimen to keep the blood thin, control blood pressure and reduce hyperlipidemia. However, 5 days post-discharge, the woman was presented again at the emergency department with the primary complaint being that of sudden onset of breathing difficulty. According to her husband’s statement, the woman had probably forgotten to take some of the prescribed medication, had undergone stress due to current heat wave, and had exerted herself while making preparations for the ensuing Christmas celebrations. Vital signs as registered on arrival at the emergency facility included a respiratory rate of 28, heart rate of 130 suggestive of rhythm sinus tachycardia, a B.P. of 140/100, oxygen saturation of 94% on 6 litre oxygen via facemask and a capillary refill value greater than 3 seconds. On palpation her skin felt cold as well as clammy. Upon lung auscultation, bilateral fine crackles were discernible. Immediate treatment recommended and provided at this stage was in the form of GTN (Nitroglycerine) infusion and an IV diuretic, frusemide at a dose of 40 mg after which she was shifted to the ICU. In the ICU, sinus tachycardia was observed along with a HR (Heart Rate) of 133. ECG (electrocardiograph) revealed resolving acute anterior septal myocardial infarction with present Q wave. She had marked hypotension with a value of 85/70 and JVP was estimated at 6 cms above the sternal angle. Echocardiography revealed an ejection fraction of 50% with poor diastolic filling. Respiration was shallow and tachypnoeic with a RR of 35. Despite a supplement of 10L/Nonbreathing mask oxygen therapy, she continued to maintain poor oxygen saturation at 80-90%. Her pain score was determined as 5/10 and the urine output was 200mls. GTN infusion was discontinued and she was put on dobutamine at a dose rate of 500 mg/100 mls in 5% dextrose titrated to a MAP of 70 mm Hg. Mask CPAP was initiated. The woman’s age, BMI and the clinical symptoms presented clearly show that she is at a clear risk of a sudden onset heart attack which has occurred according to her presented symptoms on admission at the emergency facility. Such acute heart failure syndromes (AHFS) are a recognized reason for the high rise of cases needing hospitalization over the last few decades due to rising incidence of lifestyle diseases (Coons et al, 2009). The risk of mortality is high in such cases and therapy has to be instituted immediately. The above patient’s history, signs and investigative laboratory scores clearly show that she is suffering from acute onset heart failure. Her low BP (85/70), evidence of sinus tachycardia (HR 133), poor diastolic filling suggestive of reduced left ventricular ejection fraction (LVEF), low RR (35) and poor oxygen saturation despite artificial support are clear markers for her diagnosis (Coons et al, 2009). Although the above signs are sufficient for establishing diagnosis of AHFS, it has been suggested that newer diagnostic markers such as cardiac troponin and B-type natriuretic peptide levels can assist in establishing a positive diagnosis and should be employed (Pulkki et al, 2009). The two marked symptoms as showing in the above patient which definitely point towards the diagnosis of acute heart failure are the rapidly falling BP and her tachypnoeic state with poor oxygen saturation. A weakened heart after myocardial infarction coupled with hyperlipidemia and hypertension can compromise normal physiological processes in an aged patient leading to acute onset heart failure. The pathophysiologic process involves markedly reduced cardiac output which activates neurohormonal compensatory mechanisms within the body aimed at offsetting this imbalance (Makaritsis et al, 2006). The transient hypotension caused by reduced myocardial contractility in such patients causes a marked reduction in the stroke volume leading to changes in cardiac output, end-diastolic pressure and pre/after load on the heart (Hodt et al, 2006). The renin-angiotensin-aldosterone, sympathetic and endothelin pathways are activated which result in sodium and water retention, renal and peripheral vasoconstriction with a further demand on cardiac workload (Makaritsis et al, 2006). Thereby a vicious cycle ensues which deteriorates the patient’s condition at an alarming rate unless medical assistance is provided in the form of medications to maintain adequate tissue perfusion and oxygenation with external ventilator support. Kidney is a primary organ which tries to offset the imbalance caused by reduced cardiac output, but the compensatory mechanisms have a limit beyond which the vicious cycle of reduced peripheral resistance and overcompensation by the sympathetic pathways cause drastic fall in blood pressure resulting in increases tissue oxygen demand. These are exhibited as the symptoms of hypotension and respiratory distress as exhibited by this patient. When the failing heart does not meet the required tissue perfusion levels in the body there is a risk of impending shock i.e. the failure of adequate tissue oxygenation (Wardrope & Mackenzie, 2004). In cases of acute heart failure as in this particular patient, classic signs are exhibited such as prolonged capillary refill, tachycardia, tachypnoea and the associated sympathetic nervous stimulation which manifests in the form of pallor, clammy skin, cold sweat and peripheral vasoconstriction (Wardrope & Mackenzie, 2004). Hypoxaemia is known to trigger the release of endothelin-I which alters the blood pressure control in such patients (Kuniyoshi et al, 2009). The rapid heart rate (tachycardia)needs to be controlled with beta blockers and the fall in blood pressure needs to be checked by different drugs such as ACE inhibitors/aldosterone antagonists, along with cardiotonics like digoxin depending upon the clinical signs and peculiar condition of individual patients(Muth et al, 2009). The primary therapeutic modalities employed during an acute heart failure include restoration of cardiac function and rhythm, restoration of normal blood pressure and adequate ventilation to restore proper oxygenation of the tissues. Arterial oxygen saturation of at least 95% is desirable in a patient undergoing an acute heart attack and this can be achieved through treatment with continuous positive airways pressure (CPAP) ventilator support in order to optimize oxygen saturation (Hodt et al, 2006). As pulmonary edema is usually a complication in such patients, exhibited by the discernible crackles at auscultation, CPAP is considered as a better and more efficacious procedure for restoration of oxygen levels as compared to the invasive procedure of endotracheal intubation (Hodt et al, 2006). Adequate oxygenation is the foremost concern while handling a case of acute heart failure and rest of the symptoms can be handled by concurrently administered pharmacologic interventions. The heightened respiration rate as exhibited by the above patient, low oxygen saturation level in blood and the crackles observed during auscultation suggest that there is an increased oxygen demand which needs to be handled immediately. The decision to initiate CPAP is therefore most appropriate as any delay can lead to anoxic damage to the tissues disturbing homeostasis and could be even be fatal if anoxic damage occurs in the brain. Although additional pharmacologic interventions are required to address the issue of the rapidly falling blood pressure and tachycardia, adequate oxygenation through CPAP can assist in the recovery of normal values for both these parameters as adequate oxygenation and perfusion of vital organs is necessary for recovery of spontaneous homeostatic mechanisms. Cardiac oxygen demand is high in patients suffering from cardiovascular disorders precipitated by cardiomyopathy and conditions such as sleep apnea and CPAP has been established to be the first line treatment for preventing further damage to the heart and improve patient prognosis (Peker et al, 2009). References Coons, J.C., McGraw, M. & Murali, S. (2011) Pharmacotherapy for acute heart failure syndromes, Am. J. Health-Syst Pharm., Vol. 68, pp. 21-35 Hodt, A., Steine, K. & Atar, D. (2006) Medical and Ventilatory Treatment of Acute Heart Failure: New Insights, Cardiology, Vol. 106, pp. 1-9 Kuniyoshi, F.H.S., Pusalavidyasagar, S., Singh P. & Somers, V.K. (2009) Cardiovascular consequences of obstructive sleep apnoea, Indian J. Med. Res., Vol. 131, pp. 196-205 Makaritsis, K.P., Liakopoulos, V., Leivaditis, K. et al (2006) Adaptation of Renal Function in Heart Failure, Renal failure, Vol. 28, pp. 527-535 Muth, C., Gensichen, J., Beyer, M. et al (2009) The Systematic Guideline Review: Method, rationale, and test on chronic heart failure, BMC Health Services research, Vol. 9 (74), pp.1-15 Peker, Y., Glantz, H., Thunstrom, E. et al (2009) Rationale and design of the Randomized Intervention with CPAP in Coronary Artery Disease and Sleep Apnoea-RICCADSA trial, Scandinavian cardiovascular Journal, Vol. 43, pp. 24-31 Pulkki, K., Suvisaari, J., Collinson, P. et al (2009) A pilot survey of the use and implementation of cardiac markers in acute coronary syndrome and heart failure across Europe, Clin. Chem. Lab. Med., Vol. 47 (2), pp. 227-234 Wardrope, J. & Mackenzie, R. (2004) The System of Assessment and Care of the Primary Survey Positive Patient, Emerg. Med. J., Vol. 21, pp.216-225 Read More