Routine blood tests like haemoglobin, creatinine, electrolytes are useful to plan treatment. More recently the blood natriuretic peptide levels have been used to assess heart failure. BNP (brain natriuretic peptide) may be increased early in left ventricular dysfunction. It is synthesized mainly by the ventricles and released early in heart failure.

The Framingham study group has come out with criteria for diagnosis of heart failure incorporating symptoms, signs, investigations and response to treatment. It is a useful criteria for the clinicians.

Major Criteria

 Paroxysmal nocturnal dyspnoea
 Neck vein distention
 Rales
 Radiographic cardiomegaly
 Acute pulmonary edema
 S3 gallop
 Central venous pressure >16 cm H2O
 Circulation time >25 sec
 Hepatojugular reflux
 Pulmonary adema, visceral congestion, or cardiomegaly at autopsy
 Weight loss >4.5 kg in 5 days in response to treatment of congestive heart failure.

 Minor Major

 Bilateral ankle edema
 Nocturnal cough
 Dyspnoea on ordinary exertion
 Hepatomegaly
 Pleural effusion
 Decrease in vital capacity by one third from maximal value recorded
 Tachycardia (rate >120 beats/min)

 Note: The diagnosis of congestive heart failure in this study required that two majoror one major and two minor criteria be present concurrently. Minor criteria were acceptable only if they could not be attributed to another medical condition.