Case Study 8: Heart Failure

Transcription

1 Case Study 8: Heart Failure April 2000

2 Scenario Mr James is a 68 year old man who presents to you for the first time complaining of increasing shortness of breath on exertion. He was prescribed frusemide 40mg in the morning about one year ago for swollen ankles, and has been taking it intermittently. He also has some osteoarthritis managed with diclofenac 50mg twice daily, when required. From clinical signs and an echocardiogram showing left ventricular systolic dysfunction, the diagnosis of systolic heart failure is made. You decide to initiate an ACE inhibitor. Inside Results In summary page In detail page 4 Expert commentaries A/Professor Peter MacDonald page 9 Dr Mark Morris page 2 Reference page 4 2

3 Case Study Results Results in summary One thousand four hundred and twenty eight responses have been received to this case study and the aggregate results of one hundred responses have been compiled for feedback. All respondents identified risk factors for heart failure and gave lifestyle advice for the management of the condition. Most respondents specified at least one of the therapeutic goals of ACE inhibitor therapy. 84% of respondents used starting doses of ACE inhibitor therapy which were low doses and these were in accordance with those recommended in Therapeutic Guidelines: Cardiovascular rd edition. The most commonly prescribed ACE inhibitors were perindopril 2mg daily (8%)* and lisinopril 2.5mg daily (2%)*. 90% of respondents prescribed target maintenance doses, which have demonstrated mortality benefits. Most commonly prescribed maintenance therapy were perindopril 4-8mg daily (9%)* and lisinopril 20-40mg daily (7%)*. Most respondents chose to continue frusemide as an adjunct to ACE inhibitor therapy (86%)*. Frusemide 40mg daily was the most common choice (55%)* while 6% chose low dose frusemide 20-40mg daily. Regular monitoring of blood pressure, signs of peripheral oedema, urea & electrolytes and serum creatinine / renal function were most commonly instituted by the respondents. 8% of the respondents identified the need to cease or minimise use of diclofenac (a NSAID) in a patient with heart failure. * Figure in brackets denotes percentage of respondents

4 Results in detail Question What lifestyle advice would you give Mr James? 95% of respondents would discuss or more non-pharmaceutical measures with Mr James. These responses are listed below. Lifestyle Advice Percentage of Respondents * Sodium restriction 87 Exercise: moderate, regular or graded 8 Weight reduction and/or low fat diet 79 Fluid restriction to.5 litres per day 67 Cessation of smoking 40 Cessation /reduction of alcohol intake 25 Monitoring daily weight 2 Monitoring blood pressure, diabetes, cholesterol levels Nutritional advice 4 A structured educational program 2 Other 4 * Respondents may have indicated more that one response Question 2 What is the therapeutic goal of the ACE inhibitor therapy? 96% of respondents were able to identify one or more goals of ACE inhibitor therapy. These responses are summarized in the table below. Goals of ACE inhibitor Percentage of Respondents * To improve prognosis 5 To reduce symptoms /to reduce morbidity 5 To reduce the rate of hospitalistion To improve exercise tolerance 2 To improve quality of life 27 To reduce mortality 25 To improve cardiac function /LVF 20 To aim for highest tolerated dose 5 To reduce afterload on myocardium 7 Other 5 * Respondents may have indicated more that one response 4

5 Question What would you prescribe as initial ACE inhibitor therapy? 84% of respondents initiated starting doses of ACE inhibitor, which corresponded to those outlined in the Therapeutic Guidelines: Cardiovascular rd edition. The responses are shown in the table below. ACE inhibitor Brand name Recommended starting dose Respondent choices of starting doses Perindopril Coversyl 2mg daily 2mg daily 2-4mg daily Lisinopril Prinivil, Zestril 2.5mg daily 2.5mg daily 5mg daily 0mg daily ** Ramipril Enalapril Captopril Ramace, Tritace Amprace, Renitec Acenorm, Capace, Capoten, Captohexal, DBL, Enzace, SBPA.25mg daily 2.5mg daily 6.25mg BD.25mg daily mg daily 2.5mg daily 2.5mg daily 2.5 mg BD 5mg daily 6.25mg BD 2.5mg BD Percentage of respondents* Fosinopril Monopril 5mg daily 5mg daily 5 Quinapril Accupril, Asig 2.5mg daily 2.5mg daily 5mg daily Trandolapril Gopten, Odrik 0.5mg daily 0.5mg daily 2 * 2 respondents made choices ** Lisinopril 0mg daily may have been in error

6 Question 4 What would be your target maintenance dose of ACE inhibitor? 90% of respondents prescribed target maintenance doses, which corresponded to those outlined in the Therapeutic Guidelines: Cardiovascular rd edition. The responses are shown in the table below. ACE inhibitor Brand name Recommended target maintenance dose Respondent choices of target maintenance dose Perindopril** Coversyl 4-8mg daily 2mg daily 2-4mg daily 4mg daily 4-8mg daily 8mg daily Lisinopril Prinivil, Zestril 20-40mg daily 20-40mg daily 0-40mg daily 40mg daily Ramipril Enalapril Captopril Ramace, Tritace Amprace, Renitec Acenorm, Capace, Capoten, Captohexal, DBL, Enzace, SBPA 5-0mg daily 0-20mg daily 50mg TDS 2.5mg daily 5mg daily 5-0mg daily 0mg daily 0mg daily or BD 0-20mg daily 0-20mg BD 20mg daily 50mg BD 50mg TDS Fosinopril Monopril 20-40mg daily 20mg daily 20-40mg daily Quinapril Accupril, Asig 20-40mg daily 5mg daily 0-20mg BD 20mg daily 20-40mg daily Percentage of respondents* Trandolapril Gopten, Odrik 2-4mg daily 2-4mg daily 2 * 2 respondents made choices ** respondent changed from low dose captopril to perindopril target dose

7 Question 5 Would you continue the frusemide? 86% of respondents chose to continue the frusemide as an adjunct to ACE inhibitor therapy. 2% elected not to continue it and 2% did not specify. Of the 2% that choose not to continue frusemide, 9% offered a reason. Examples of such included waiting to see if the ACE inhibitor controlled symptoms and waiting until the target dose was reached. If it was required, 2 respondents chose low dose frusemide while 2 other respondents chose indapamide. Question 6 If so, at what dose? 55% of respondents chose to continue frusemide 40mg daily and 6% chose low dose frusemide 20-40mg. 97% of respondents chose a frequency of daily for the frusemide. The total daily doses chosen are shown in the table below. Total daily dose of frusemide (mg) Percentage of Respondents 40mg mg 20 20mg mg 7 80mg 40-20mg Question 7 What monitoring would you institute? All respondents would monitor one or more clinical signs. Clinical signs Percentage of Respondents * Blood pressure /hypotension 69 Ankle oedema /oedema /peripheral oedema 59 Bibasal creps /lung crepitations /breath sounds /crackles 52 /pleural effusion Weight 48 Jugular venous pressure 9 Pulse-rate, rhythm 26 Degree of dyspnoea /SOB /orthopnea /paroxysmal nocturnal 24 dyspnoea/cough Heart sounds /triple rhythm /S Exercise capacity 7 Cardiomegaly 6 Hepatomegaly /splenomegaly 5 Signs of heart failure (unspecified) 5 Other * Respondents may have made more than one response. 7

8 97% of respondents would investigate biochemistry. Biochemistry Percentage of Respondents * Urea & electrolytes 98 Creatinine /renal function 74 Full blood count (including Hb) 2 Liver function tests 7 Lipid profile 7 Blood sugar levels 6 Erythrocyte sedimentation rate /CRP 2 Urinary microalbumin 2 Thyroid function tests Urine analysis Unspecified *Respondents may have made more than one response Question 8 What medication counselling would you give to the patient? 99% of respondents would provide medication counselling. 8% of respondents would cease or minimise diclofenac (a NSAID) and of these most would offer regular paracetamol as an alternative. A summary of responses is shown below. Medication Counselling Percentage of Respondents * Cease or minimise diclofenac (a NSAID) 8 Explain need for regular, indefinite ACE inhibitor /diuretic 6 therapy Explain side-effects of drugs & instruct to report if occur 27 Suggested regular physical examination & biochemistry 4 Report concurrent use of other medication including OTC 4 Report if cough develops 4 Watch for first dose hypotension 4 Suggested non-pharmacological treatments of OA Explain potential changes to medication & dosages Avoid potassium supplements 2 Take asprin regularly Do not alter medications Prescribed Fluvac & Pneumovax *Respondents may have made more than one response 8

9 Expert commentary Associate Professor Peter MacDonald Staff Cardiologist, St Vincent s Hospital, Sydney. The case history presents both diagnostic and therapeutic issues. Only the therapeutic issues have been addressed in detail by the questions posed about this case. The diagnosis of heart failure due to systolic left ventricular dysfunction is clear enough from the information provided, however the underlying pathological process that has caused the LV dysfunction has not been determined. The most likely cause in our community is ischaemic heart disease, but long-standing hypertension or some form of dilated cardiomyopathy are also possibilities. A history of angina, myocardial infarction, hypertension, other coronary risk factors should be sought and alcohol consumption assessed. The overall case study results indicate that the vast majority of GPs have a clear understanding of the importance of life-style modifications and the appropriate use of ACE inhibitors in patients with heart failure. The importance of non-steroidal antiinflammatory drugs as a precipitant of heart failure has been recognised as has the importance of regular monitoring of blood pressure and signs of fluid retention, and simple blood tests to measure electrolytes and creatinine. The optimal use of ACE inhibitors, diuretics and beta-blockers in patients with heart failure is critically dependent on this type of monitoring. Question What lifestyle advice would you give Mr James? I would emphasize the importance of salt restriction and encourage regular low intensity exercise. His ability to exercise may be limited by his osteoarthritis and it would be necessary to establish his limitations due to OA before embarking on a course of exercise. A physiotherapist should be able to provide an appropriately structured exercise program which takes into account restrictions caused by other disabilities. Fluid restriction in addition to salt restriction is usually only required in patients with intractable oedema. The patient should be screened for all coronary risk factors and advised to stop smoking if this is the case. Alcohol should be minimised or stopped completely if an alcoholic cardiomyopathy is considered likely. 9

10 Question 2 What is the therapeutic goal of the ACE inhibitor therapy? The goals of ACE inhibitor therapy are multiple and vary according to the individual. For example, prolongation of life is clearly a major goal in this 68 year old man, but may not be if he were 88 years old. Improvement in quality of life and prevention of the need for hospitalisation are important goals of ACE inhibitors in all patients. Improvements in exercise tolerance and cardiac function are usually modest, but are important in as much as they contribute to the patients improved quality of life and symptomatic stability. Question What would you prescribe as initial ACE inhibitor therapy? The patient should be started on an ACE inhibitor in low dose. Although the benefits of ACE inhibitors are almost certainly a class effect, my preference is to choose a once daily ACE inhibitor in order to facilitate compliance. Question 4 What would be your target maintenance dose of ACE inhibitor? The target dose of ACE inhibitor should be that which has been shown to be effective in clinical trials. The majority of respondents have answered this question appropriately. Surveys of prescriptions written for heart failure drugs suggest, however, that most ACE inhibitors are prescribed in low doses. Question 5 Would you continue the frusemide? I would continue to prescribe frusemide in this patient. It is tempting to think that use of a single agent such as an ACE inhibitor may be sufficient to control a patient s symptoms. Most patients with symptoms and signs of fluid retention do require a diuretic to achieve optimal symptomatic control. Question 6 If so, at what dose? It may be possible to reduce the dose of frusemide, but as stated above in response to Question 5, it is unlikely that the patient will remain asymptomatic on an ACE inhibitor alone. Concurrent diuretic administration renders patients more prone to symptomatic hypotension after the introduction of an ACE inhibitor. It would be important to check the patients blood pressure, serum sodium and creatinine prior to commencement of an ACE inhibitor. If the blood pressure or serum sodium is low, or the serum creatinine is elevated, I would halve frusemide dose at the time of commencement of the ACE inhibitor. 0

11 Question 7 What monitoring would you institute? Clinical and laboratory parameters are both important in judging the response to heart failure therapy. Blood pressure is obviously important in determining the use and dose of ACE inhibitor. Caution is required in patients with a systolic BP<00mmHg and any patient with a systolic BP<90mmHg prior to introduction of an ACE inhibitor should be referred to a specialist. Symptoms and signs of fluid retention are important in determining the dose of diuretics and the use of beta-blockers. Betablockers should only be administered to patients who have been rendered euvolaemic. Regular monitoring of electrolytes and renal function is important in patients receiving diuretics and ACE inhibitors, particularly during changes in therapy. Measurement of serum lipids, glucose, haemoglobin and thyroid function tests are important in the initial diagnostic evaluation, but need not be repeated on a regular basis unless abnormal or new symptoms develop. Question 8 What medication counselling would you give to the patient? The importance of NSAIDs as a precipitant of heart failure has been identified by the majority of GPs and I would certainly advise the patient to stop this medication. COX-2 inhibitors have no advantages in this patient and paracetamol is probably the safest alternative. I believe that some time is needed to explain the rationale for the use of an ACE inhibitor, possible side-effects including first dose hypotension (and how the risk of this may be minimised eg by taking the first dose at night before bed) and cough, and the need to continue this treatment permanently. The importance of regular medical follow-up also needs to be emphasized.

12 Dr Mark Morris General Practitioner, Spring Hill, Queensland Mr James sounds all too familiar; a male patient presenting in his sixties or older with a history of increasing shortness of breath on exertion. There is often a history of smoking and hypertension but we are not given this information. The most likely causes of his heart failure are ischaemic heart disease and hypertension and both conditions may be present. This is based on the fact that 90% of all cases of heart failure are due to hypertension and ischaemic heart disease. There may be a few clinical signs of heart failure and I would stress the importance of moving on to an echocardiogram early to prove or disprove the diagnosis and assess the severity and cause. Question What lifestyle advice would you give Mr James? In the hurry to get a patient on medication, lifestyle advice can easily be forgotten and I was pleased to see in the responses to question that 95% of respondents would discuss or more non-pharmaceutical measures with Mr James. The important interventions were all mentioned: smoking cessation, alcohol reduction or cessation, weight reduction if overweight, sodium restriction, moderate regular exercise when heart failure stable, fluid restriction in patients with hyponatraemia and monitoring weight. Question 2 What is the therapeutic goal of the ACE inhibitor therapy? ACE inhibitors should be prescribed in all patients with heart failure, unless there is a specific contraindication. ACE inhibitors improve prognosis, reduce hospital admissions and improve quality of life and the answers to the questions on ACE inhibitors indicate that the respondents are aware of the benefits. Question What would you prescribe as initial ACE inhibitor therapy? Question 4 What would be your target maintenance dose of ACE inhibitor? The importance of starting at a low dose and titrating up is understood but I would like to stress the importance of titrating to the maximum dose over to 4 weeks. If the patients becomes hypotensive while titrating up then the appropriate response is usually to reduce the diuretic and not the ACE inhibitor. Remember to monitor renal function and electrolytes and that careful dosage titration and closer monitoring is required in the elderly. Generally, ACE inhibitors still tend to be under used and prescribed in suboptimal doses. 2

13 Question 5 Would you continue the frusemide? Question 6 If so, at what dose? Like the majority of respondents, I would continue frusemide as an adjunct to the ACE inhibitor therapy. The frusemide would contribute to the control of the signs and symptoms of heart failure. The dose of frusemide may need to be reduced to 20mg daily as the dose of ACE inhibitor is increased. Question 7 What monitoring would you institute? Monitoring heart failure patients must include checking renal function, electrolytes and blood pressure, and this was identified by the majority of respondents. In addition to this, patients should be regularly assessed for signs and symptoms of heart failure and have other pathology checks periodically or when indicated e.g. full blood count, liver function tests, blood glucose, lipids and thyroid function tests. Asking patients to check their weight daily provides an extra guide on clinical status and treatment response. Question 8 What medication counselling would you give to the patient? The message has been around for years and is obviously well known that NSAIDs can exacerbate heart failure. I agree with the majority of respondents that diclofenac should be stopped if possible and I would try using regular paracetamol and nonpharmacological measures to control his symptoms of osteoarthritis. Unfortunately, the new selective COX-2 inhibitors appear to cause the same problems in heart failure as the older NSAIDs. Respondents also identified the important issue of encouraging compliance with antifailure therapy, including reporting side effects. Reminding patients to discuss over-the-counter and complementary medications before taking them is important. Over-the-counter NSAIDs and potassium supplements are not uncommon discoveries when asking heart failure patients about other tablets, vitamins, tonics or supplements that they take. Vaccination annually with the influenza vaccine and 5 yearly with Pneumovax was mentioned and should be given. Treatment of heart failure and underlying disease(s) and risk factors does involve an increasing number of medications. In this case, Mr James would also be considered for a beta-blocker e.g. carvedilol, and he may also require lipid lowering medication and other medication. Compliance could be a significant issue and it is obviously important to involve Mr James in decisions about his treatment and continue to check compliance. Promptly address side-effects and reinforce the benefits of treatment at follow-up visits.

14 Reference. Therapeutic Guidelines: Cardiovascular, rd edition. North Melbourne: Therapeutic Guidelines Limited, 999:-25 4