3.3: Clinical aspects

History

A careful history of the patient is important for the diagnosis and in order to identify the cause of HF. The history (and physical examination) can be used to differentiate between the abovementioned potential causes of HF (refer to Etiology of heart failure). Family history of HF, smoking status, hyperlipidaemia, hypertension and diabetes mellitus are factors that should be taken into account during the assessment of the patient history in order to draw a risk profile of the patient. Finally, the history should include previous events and the response to therapy.

Symptoms and signs

HF can manifest with a multitude of different symptoms and signs, but shortness of breath and tiredness are the most characteristic. The Framingham Heart Study defined major and minor diagnostic criteria for HF.

Major criteria:

• Paroxysmal nocturnal dyspnea
• Neck vein distention
• Pulmonaty rales
• Radiographic cardiomegaly (increasing heart size on chest radiography)
• Acute pulmonary edema
• S3 gallop
• Increased central venous pressure (>16 cm H2O at right atrium)
• Hepatojugular reflux
• Weight loss >4.5 kg in 5 days in response to treatment

Minor criteria:

• Bilateral ankle edema
• Nocturnal cough
• Dyspnea on ordinary exertion
• Hepatomegaly
• Pleural effusion
• Tachycardia (heart rate>120 beats/min.)

Minor criteria are acceptable only if they cannot be attributed to another medical condition (such as pulmonary hypertension, chronic lung disease, cirrhosis, ascites, or the nephrotic syndrome).

Diagnosis of HF requires the simultaneous presence of at least 2 major criteria or 1 major criterion in conjunction with 2 minor criteria. The Framingham Heart Study criteria are 100% sensitive and 78% specific for identifying persons with definite congestive heart failure in an outpatient population.[7]

Severity of HF

In general, correlation between the severity of symptoms and the severity of HF in terms of loss of maximal oxygen consumption is weak.[3] The New York Heart Association functional classification is used most frequently to classify the severity of HF (Table 3.3.1). Assessing severity is needed for the proper therapy/ medication to be chosen.

Table 3.3.1: NYHA functional classification

Severity Based on Symptoms and Physical Activity
Class I	No limitation of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, or dyspnoea.
Class II	Slight limitation of physical activity. Comfortable at rest, but ordinary physical activity results in fatigue, palpitation, or dyspnoea.
Class III	Marked limitation of physical activity. Comfortable at rest, but less than ordinary activity results in fatigue, palpitation, or dyspnoea.
Class IV	Unable to carry on any physical activity without discomfort. Symptoms at rest. If any physical activity is undertaken, discomfort is increased.

Physical examination

There are several key features in the clinical examination of a patient presenting with HF. The physical examination should focus on the general appearance of the patient, pulse and blood pressure, signs of fluid overload (increased jugular venous pressure, peripheral edema, ascites and hepatomegaly), the lungs, and the heart (apex, Gallop rhythm, third heart sound, murmurs).

Figure 3.3.1: Flowchart suspected heart failure [3]

Additional diagnostic tests

In order to assist in the diagnosis of HF and to differentiate between possible causes of HF, the following tests are available.

Electrocardiogram

An electrocardiogram (ECG) should be performed on every patient suspected of HF. Several common abnormalities (including possible causes) indicative of HF on the ECG include but are not limited to: sinus tachy- or bradycardia, atrial tachycardia, -flutter, or –fibrillation, ventricular arrhythmias, ischemia (including myocardial infarction), abnormal Q waves, left ventricular hypertrophy, micro voltages, and QRS length >120 ms. Although an abnormal ECG (excluding arrhythmias) has a low positive predictive value for HF, a normal ECG is highly indicative of the absence of HF.

Chest X-ray

A chest X-ray is a part of the standard examination in potential HF patients. Importantly, the X-ray is a tool to detect cardiomegaly (defined as a cardiac: thoracic ratio of > 0,5) or other clues (redistribution, Kerley B-lines and pleural effusion) that indicate HF. It is also important to rule out other causes of dyspnea.

Echocardiography

Echocardiography is the cornerstone in the diagnosis of HF, and should be performed routinely, because ventricular function can be evaluated accurately with this technique. It can provide objective evidence of a structural or functional abnormality of the heart at rest, besides signs and symptoms that are typical of heart failure. Important parameters that can be assessed include, but are not limited to, wall motion, valve function, left ventricular ejection fraction and diastolic function. Diastolic dysfunction might be an important finding in symptomatic patients with a preserved ejection fraction. Refer to Table 3.3.2 for common echocardiographic findings in HF. Transesophageal echocardiography is indicated in patients with an inadequate transthoracic echo window, suspected endocarditis, complicated valvular disease or to exclude a LV thrombus. If echocardiography provides inadequate information or in patients with suspected coronary artery disease, additional imaging includes CT scanning, cardiac magnetic resonance imaging or radionuclide imaging.

Table 3.3.2: Common echocardiographic abnormalities in heart failure

Measurement	Abnormality	Clinical Implications
Left ventricular ejection fraction (LVEF)	Reduced (< 50%)	Left ventricular global systolic dysfunction
Left ventricular wall motion	Akinesis, hypokinesis, dyskinesis	Myocardial infarction/ischaemia, Cardiomyopathy, Myocarditis
Left ventricular end-diastolic diameter	Increased (≥60 mm/>32 mm/m2))	Volume overload HF likely
Left ventricular end-systolic diameter	Increased (≥45 mm/>25 mm/m2,)	Volume overload, HF likely
Left ventricular fractional shortening	Reduced (<25%)	Left ventricular systolic dysfunction
Left atrial volume index	Increased (volume >34 mL/m2)	Increased filling pressures, Mitral valve dysfunction
Left ventricular thickness	Hypertrophy (>11 – 12 mm)	Hypertention, Aortic stenosis, Hypertrophic cardiomyopathy
Valvular structure and function	Valvular stenosis or regurgitation (especially aortic stenosis and mitral insufficiency)	May be primary cause of HF or complicating factor, Assess haemodynamic consequences, Consider surgery
Mitral diastolic flow profile	Abnormalities of the early and late diastolic filling patterns	Indicates diastolic dysfunction and suggests mechanism
Tricuspid regurgitation peak velocity	Increased (>3.4 m/s)	Increased right ventricular systolic pressure
Pericardium	Effusion, Haemopericardium, Calcification	Consider tamponade, Malignancy, Systemic disease, Acute or chronic pericarditis, Constrictive pericarditis
Aortic outflow velocity time integral	Reduced (<15 cm)	Reduced low stroke volume
Right ventricular function (e.g. TAPSE)	Reduced (TAPSE < 16 mm)	RV systolic dysfunction
Inferior vena cava	Dilated, with no respiratory collapse	Increased right atrial pressures, Right ventricular dysfunction, Volume overload, Pulmonary hypertention possible

Laboratory tests

A standard blood assessment includes a complete blood count, electrolytes, renal function, glucose and liver function. Furthermore, urinalysis and other tests, depending on the clinical condition of the patient, complete the laboratory assessment. For example, cardiac troponins must be sampled if an ACS is in the differential diagnosis. In patients suspected of HF, values of natriuretic peptides (such as B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP)) can provide important information regarding the diagnosis, management and prognosis of HF. Natriuretic peptides are enzymes, secreted by the atria or ventricles in response to myocardial wall stress. The most commonly used tests are BNP and NT-proBNP measurements, which despite their different half-lives in the plasma, do not differ substantially in terms of diagnostic ability. Cut-off values are different in acute settings with acute dyspnea compared to chronic settings. Normal values are almost 100% specific, and exclude heart failure in patients >18 year old. Abnormal values do not have a 100% predictive value, and objective evidence for heart failure is still needed. The values for BNP and NTproBNP are also used to evaluate the prognosis in patients with known HF, in whom higher values carry a worse prognosis.

Exercise test

An exercise test is not diagnostic for HF, but may be used to identify ischemia as the cause of heart failure, or it can be used to assess the severity of HF, usually in conjunction with maximal oxygen uptake (VO_2max) measurement. This test is performed on a treadmill or on a bicycle ergo meter. The patient is asked to give maximal effort while the workload gradually increases. During the test, the ECG is monitored for ischemia. When possible, oxygen consumption should also be measured during the test. Not only is an oxygen consumption test a good tool to discriminate between lung- peripheral- or heart problems, but the obtained value for maximal oxygen uptake (VO_2max) has an important prognostic value.

Heart catheterization

Heart catheterization is not always part of the routine diagnosis and work-up of patients with HF. It should be considered however to exclude coronary heart disease (Class of recommendation IIa, level of evidence C, see Table 3.3.3). Coronary angiography is recommended in patients at high risk of coronary artery disease (Class of recommendation I, level of evidence C) and in HF patients with significant valvular disease (Class of recommendation IIa, level of evidence C).

Table 3.3.3: Size of treatment effect.

	Class I Benefit >>> Risk	Class IIa Benefit >> Risk Additional studies with focused objectives needed	Class IIb Benefit ≥ Risk Additional studies with broad objectives needed; additional registry data would be helpful	Class III Benefit ≥ Risk No additional studies needed
	>> Risk" class="lt-med-42735">Procedure/treatment should be performed/administered	> RiskAdditional studies with focused objectives needed" class="lt-med-42735">It is reasonable to perform/administer treatment	Procedure/treatment may be considered	Procedure/treatment should not be performed/ administered since it is not helpful and may be harmful
Level A Multiple (3-5) population risk strata evaluated	>> Risk" class="lt-med-42735"> Recommendation that procedure or treatment is useful/effective Sufficient evidence from multiple randomized trials or non-randomized trials	> RiskAdditional studies with focused objectives needed" class="lt-med-42735"> Recommendation in favor of treatment or procedure being useful/effective Some conflicting evidence from multiple randomized trials or meta-analyses	Recommendation’s usefulness/efficacy less well established Greater conflicting evidence from multiple randomized trials or meta-analyses	Recommendation that procedure or treatment not useful/effective and may be harmful Sufficient evidence from multiple randomized trials or meta-analyses
Level B Limited (2-3) population risk strata evaluated	>> Risk" class="lt-med-42735"> Recommendation that procedure or treatment is useful/effective Limited evidence from single randomized trial or non-randomized studies	> RiskAdditional studies with focused objectives needed" class="lt-med-42735"> Recommendation in favor of treatment or procedure being useful/effective Some conflicting evidence from single randomized trial or non-randomized studies	Recommendation’s usefulness/efficacy less well established Greater conflicting evidence from single randomized trial or non-randomized studies	Recommendation that procedure or treatment not useful/effective and may be harmful Limited evidence from single randomized trial or non-randomized studies
Level C Very limited (1-2) population risk strata evaluated	>> Risk" class="lt-med-42735"> Recommendation that procedure or treatment is useful/effective Only experts opinion, case studies, or standard-of-care	> RiskAdditional studies with focused objectives needed" class="lt-med-42735"> Recommendation in favor of treatment or procedure being useful/effective Only diverging expert opinion case studies, or standard-of-care	Recommendation’s usefulness/efficacy less well established Only diverging expert opinion case studies, or standard-of-care	Recommendation that procedure or treatment not useful/effective and may be harmful Only expert opinion case studies, or standard-of-care