Diastolic congestive heart failure is reviewed here.
Diastolic dysfunction occurs when the left ventricular myocardium is non-compliant and not able to accept blood return in a normal fashion from the left atrium. This can be a normal physiologic change with aging of the heart or result in elevated left atrial pressures leading to the clinical manifestations of diastolic congestive heart failure. There are four grades of diastolic dysfunction as described below. Echocardiography is the gold standard to diagnose diastolic dysfunction.
Grade I (impaired relaxation): This is a normal finding and occurs in nearly 100% of individuals by the age of 60. The E wave velocity is reduced resulting in E/A reversal (ratio < 1.0). The left atrial pressures are normal. The deceleration time of the E wave is prolonged measuring > 200 ms. The e/e’ ratio measured by tissue Doppler is normal.
Grade II (pseudonormal): This is pathological and results in elevated left atrial pressures. The E/A ratio is normal (0.8 +- 1.5), the deceleration time is normal (160-200 ms), however the e/e’ ratio is elevated. The E/A ratio will be < 1 with Valsalva. A major clue to the presence of grade II diastolic dysfunction as compared to normal diastolic function is the presence of structural heart disease such as left atrial enlargement, left ventricular hypertrophy or systolic dysfunction. If significant structural heart disease is present and the E/A ratio as well as the deceleration time appear normal, suspect a pseudonormal pattern. Valsalva distinguishes pseudonormal from normal as well as the e/e’ ratio. Diuresis can frequently reduce the left atrial pressure relieving symptoms of heart failure and returning the hemodynamics to those of grade I diastolic dysfunction.
Grade III (reversible restrictive): This results in significantly elevated left atrial pressures. Also known as a “restrictive filling pattern”, the E/A ratio is > 2.0, the deceleration time is < 160 ms, and the e/e’ ratio is elevated. The E/A ratio changes to < 1.0 with Valsalva. Diuresis can frequently reduce the left atrial pressure relieving symptoms of heart failure and returning the hemodynamics to those of grade I diastolic dysfunction.
Grade IV (fixed restrictive): This indicates a poor prognosis and very elevated left atrial pressures. The E/A ratio is > 2.0, the deceleration time is low and the e/e’ ratio is elevated. The major difference distinguishing grade III from grade IV diastolic dysfunction is the lack of E/A reversal with the Valsalva maneuver (no effect will be seen with Valsalva). Diuresis will not have a major effect on the left atrial pressures and clinic heart failure is likely permanent. Grade IV diastolic dysfunction is present only in very advanced heart failure and frequently seen in end-stage restrictive cardiomyopathies such as amyloid cardiomyopathy.