Reports

This report is based on medical evidence presented at sanctioned medical congress, from peer reviewed literature or opinion provided by a qualified healthcare practitioner. The consumption of the information contained within this report is intended for qualified Canadian healthcare practitioners only.

22nd Annual Cardiovascular Conference at Lake Louise

Lake Louise, Alberta / March 26-30, 2006

Dr. Malcolm Arnold, Professor of Medicine, Physiology and Pharmacology, and Research Director, Division of Cardiology, University of Western Ontario, London, presented the new 2006 Canadian Cardiovascular Society (CCS) Heart Failure Consensus Recommendations here at Lake Louise. The CCS convened the consensus conference to review new evidence and update existing guidelines where needed.

In Canada, heart failure is common, especially among older patients, and is associated with a 5% to 50% mortality rate. The guidelines therefore are designed to “review landmark cases” and provide “recommendations and practical tips,” Dr. Arnold explained.

Dr. Jonathan Howlett, Chair and Medical Director, Heart Function and Transplantation Program, Queen Elizabeth II Health Sciences Centre, and Associate Professor of Medicine, Dalhousie University, Halifax, Nova Scotia, told delegates, “These recommendations are designed to provide practical advice for specialists, family physicians, nurses, pharmacists, and other healthcare professionals involved in heart failure care.”

The guideline authors outlined the steps of heart failure management, including accurate diagnosis, individualized care, appropriate drug therapy or mechanical interventions, and patient and caregiver education.

Dr. Arnold and his colleagues stated, “Our goal is that this will improve the delivery of best care and practices to heart failure patients in Canada.” To that end, the expert panel reviewed new clinical trial evidence and meta-analyses.

The consensus recommendations are categorized by “class,” implying a degree of safety, usefulness and effectiveness (classes I-III). Class I recommendations were those that were the most beneficial, useful and effective; Class III recommendations indicated those therapies that were not shown to be useful or effective and, in some cases, even harmful. Secondly, the recommendations were graded based upon levels of evidence (levels A-C). Level A evidence was dependent upon data derived from multiple randomized clinical trials; Level C evidence represented a consensus opinion of experts or findings from small studies.

Diagnosing Heart Failure

The first step in treatment is an accurate identification of the problem and the extent of heart failure involved. The authors provided a simple diagram for diagnosing heart failure that takes into account clinical history, physical findings, clinical investigation and ventricular function, among other factors.

Among others, specific class I recommendations for diagnosis indicate that clinical history, physical exam and laboratory testing should be performed on all patients; transthoracic echocardiography should be performed to assess ventricular size; coronary angiography should be considered; functional capacity, indexed against a validated measure like the New York Heart Association (NYHA) classification, should be measured. Among the class II recommendations regarding diagnosis, the guidelines recommend that plasma B-type or brain natriuretic peptides (BNPs) should be measured, especially when clinical uncertainty exists.

With reference to BNP as a tool in diagnosing heart failure, Dr. Nadia Giannetti, Medical Director, Heart Function Centre, MUHC-Royal Victoria Hospital, and Assistant Professor of Medicine, McGill University, Montreal, Quebec, addressed the challenges, especially the ability to diagnose heart failure in the presence of comorbidities.

During an interactive presentation, Dr. Giannetti discussed a case report of a patient who presented with all of the symptoms that appeared to be heart failure, including a cough, cool extremities, mild edema, and “a messy- looking chest X-ray.” Upon further investigation, including an echocardiography and BNP test, the clinicians learned that the echocardiography showed normal function and the “BNP test came back at 20 pg/mL,” which Dr. Giannetti characterized as “a very low value.”

Although edema, fatigue and dyspnea are common symptoms associated with heart failure, there is potentially a much wider range of presenting symptoms, particularly among female, elderly, or obese patients. The common symptoms of heart failure include weakness, cough, weight gain, nocturia, cool extremities, and exercise intolerance; uncommon symptoms include nausea, abdominal discomfort, cyanosis, and anorexia.

Therefore, it was only upon further investigation and additional tests, including BNP, that heart failure as a diagnosis was ruled out. In this instance, BNP proved itself a useful tool in making the correct diagnosis in seemingly borderline cases, a finding that has been borne out by other studies (Horwich et al. J Am Coll Cardiol 2006;47:85-90). Although accessibility to BNP continues to be an issue, Dr. Giannetti advised, “In cases where the diagnosis is unclear, particularly in trying to differentiate a primary respiratory from a primary cardiac case of dyspnea, a negative BNP can be useful.”

After the diagnosis of heart failure is made, there are tests that can help assess functional capacity to determine the degree of physical limitation. A six-minute walk test, radionuclide perfusion imaging and coronary angiography are all tools that can help determine functional capacity. Endomyocardial biopsy is not typically recommended in routine heart failure.

Non-pharmacological Management of Heart Failure

Once diagnosed, the healthcare team needs to decide upon the appropriate course of action as part of the individualized care plan for the patient. In recent years, the authors cite a trend towards a consideration of exercise training programs, indicating studies that have shown increased physical capacity with proper physical training.

A practical tip for non-pharmacological management is for the patient to engage in regular physical or leisure activities while avoiding unsupervised exercise. Other recommendations include limited salt intake to a minimum based upon the level of heart failure involved. Patients should be asked to monitor their weight every morning, and fluid intake should be limited to 1.5 L to 2.0 L/day for those suffering from fluid retention.

Class I recommendations include a multidisciplinary approach to outpatient heart failure management. The authors support the use of specialized hospital-based clinics or disease management programs, where optimal care reflects local circumstances and resources. Close clinical follow-up and follow-up within four weeks are also recommended. The authors found that “patients with recent or recurrent hospital admissions for heart failure appear to benefit the most” from a multidisciplinary approach. Practically, this means that patients can be monitored through telephone calls from experienced nurses and by educating patients to weigh themselves daily and adjust their diuretic medications accordingly.

Regarding immunizations, heart failure patients should receive influenza vaccinations annually and pneumococcal pneumonia vaccine every six years or as otherwise indicated.

Optimal Strategies

Beginning with a premise of individualized care to monitor for specific contraindications, the authors provide some general recommendations for treatment.

The new consensus guidelines make class I recommendations regarding aggressive management of cardiovascular risk factors with drug therapy as well as with lifestyle modifications. Additionally, all patients with left ventricular ejection fraction (LVEF) <40% should receive an ACE inhibitor in combination with a beta blocker unless contraindicated. The target dose for these therapies should be those found to be efficacious in large-scale clinical trials, and alternative therapy regimens should be proposed if the patient is unable to tolerate the more common prescriptions. The authors noted, “In general, acute symptoms should be relieved, but an ACE inhibitor or a beta blocker should be introduced as early as the patient’s condition allows.” (Figure 1)

Because patients with heart failure are already clinically fragile, many therapies are to be used with caution so as to limit the exacerbation of heart failure. The guidelines state: “Patients with heart failure are generally elderly and have multiple comorbidities; therefore, the addition of multidrug therapy for heart failure adds to an already complex pharmacological regimen.”

“Diastolic” Heart Failure

Dr. Peter Liu, Director, Heart and Stroke/Richard Lewar Centre of Excellence in Cardiovascular Research, UHN-Toronto General Hospital, and Heart and Stroke/Polo Chair Professor of Medicine and Physiology, University of Toronto, Ontario, outlined the incidence of heart failure with preserved systolic function (PSF), also known as “diastolic heart failure.”

The new guidelines seek to correct the oversight of heart failure with PSF and address it directly. Dr. Liu described for delegates the typical patient with diastolic heart failure as “an elderly female with pre-existing hypertension, diabetes or underlying coronary disease but without a prior infarction.” He added that recent Canadian data suggest that mortality for diastolic heart failure is very similar to that of systolic heart failure.

When administered correctly, the same agents used in systolic heart failure are generally also beneficial for diastolic heart failure, including ACE inhibitors, angiotensin receptor blockers (ARBs) and beta blockers. Dr. Liu discussed the findings of the Candesartan in Heart Failure – Assessment of Reduction in Mortality and Morbidity (CHARM)-Preserved trial. The study observed patients with clinical heart failure and preserved systolic function (LVEF>40%) who were randomized to the ARB candesartan or placebo. As Dr. Liu told delegates, “The study showed an overall 11% reduction in the combined end points of death or heart failure hospitalization (P=0.12). There was also a significant reduction in investigator-reported hospitalization for heart failure and a 40% reduction in the incidence of new diabetes.” These finding suggest that ARB therapy can be useful as part of an overall strategy in the treatment of diastolic heart failure.

Arrhythmia, Acute Heart Failure

With respect to atrial fibrillation, the guidelines recommend amiodarone as the therapy of choice in achieving and With respect to atrial fibrillation, the guidelines recommend amiodarone as the therapy of choice in achieving and maintaining sinus rhythm. For those patients with an LVEF <40%, beta blocker or digoxin monotherapy or combination therapy should be considered. Unless contraindicated, the use of anticoagulation therapy is highly recommended for these patients.

The guidelines also provide strategies for addressing patients with acute heart failure (AHF), which is defined as “the rapid onset of symptoms and signs secondary to any abnormalities in cardiac function that may be life-threatening and require urgent treatment,” and can present in patients without any known cardiac dysfunction. Among the class I recommendations is the use of clinical, radiographic and biochemical evaluations to best assess the severity of the condition. Other class I recommendations indicate: “If available, blood BNP or N-terminal proBNP level should be measured if the diagnosis is in doubt;” intravenous furosemide for patients with volume overload; and the use of an arterial line for those with very low cardiac output. The use of diuretics and vasodilators may be indicated for AHF patients. Intubation may be needed to fend off impending respiratory failure.

Devices such as the implantable cardioverter defibrillator (ICD) may be useful for high-risk patients. Class I recommendations for device-based therapy include consultations by heart failure as well as arrhythmia specialists and the use of ICDs in patients with LVEF £30%. These guidelines have not changed significantly from the previous set of recommendations owing to the lack of new controlled trials in this area. The use of ICDs may also be indicated in patients needing cardiac resynchronization therapy.

With respect to surgical options, the guidelines recommend, “Heart failure remains a disease primarily addressed with medical therapy, and surgical therapy has traditionally been limited to a small minority of patients.” However, there are instances in which surgery may be indicated, such as for those patients who may benefit from a heart transplant or the use of coronary artery bypass surgery in angina patients.

Assessing Heart Failure in the Elderly Patient

Because heart failure is increasingly present among the elderly, the consensus recommendations discuss appropriate care for this patient group.

Among the class I recommendations: a full assessment of comorbidities that may be present; the identification of an appropriate caregiver; and referral to a geriatric specialist where appropriate. Healthcare providers are also encouraged to monitor for depression, a common symptom among heart failure patients, as well as signs of cognitive impairment or dementia.

Dr. Debra Isaac, Director, Cardiac Transplant Program, Foothills Medical Centre, and Associate Clinical Professor of Medicine, University of Calgary, Alberta, discussed changing patterns of care for heart failure patients from maintenance therapy to supportive care.

Supportive care and end-of-life considerations are also important for heart failure patients. “Palliative treatment for end-stage heart failure patients must include management for pain, severe dyspnea, severe congestion, cough and anxiety,” Dr. Isaac explained. The guidelines point out that quality end-of-life care has three elements: “support of dying patients and their families; control of pain and other symptoms; and decisions on the use of life-sustaining therapies.” As such, the process involves “truth-telling, consent, capacity, substitute decision-making, advance care planning and appropriate use of life-sustaining treatment.”

Summary

These consensus recommendations can provide an evidence-based road map to translate knowledge into practice.

Dr. Simon Jackson, Program Director, Adult Cardiology, and Assistant Professor of Medicine, Division of Cardiology, Queen Elizabeth II Health Sciences Centre, conducted an interactive session regarding the consensus recommendations and expressed his hopes: “We really want people to interact and communicate, using active encouragement and active reinforcement.”