From the Guidelines
Diastolic heart failure is typically classified into three grades based on the severity of diastolic dysfunction: Grade 1 (Mild): Impaired relaxation, Grade 2 (Moderate): Pseudonormal filling, and Grade 3 (Severe): Restrictive filling, as supported by the most recent evidence 1. This classification is primarily determined through echocardiography, specifically by assessing mitral inflow patterns, tissue Doppler imaging, and left atrial volume. To diagnose and classify diastolic heart failure:
- Perform a comprehensive echocardiogram, including:
- Mitral inflow velocities (E and A waves)
- Tissue Doppler imaging of the mitral annulus (e' velocity)
- Left atrial volume index
- Tricuspid regurgitation velocity
- Calculate the E/A ratio and E/e' ratio
- Interpret results:
- Grade 1: E/A ratio < 0.8, E/e' ratio < 10
- Grade 2: E/A ratio 0.8-2, E/e' ratio 10-14
- Grade 3: E/A ratio > 2, E/e' ratio > 14 Understanding this classification is crucial for appropriate management, as treatment strategies may vary based on the severity of diastolic dysfunction, as noted in previous guidelines 1. The underlying pathophysiology involves impaired left ventricular relaxation and increased left ventricular stiffness, leading to elevated left atrial pressures and potential pulmonary congestion. It is essential to consider the most recent guidelines and evidence when classifying and managing diastolic heart failure, as they provide the most up-to-date information on diagnosis, treatment, and management strategies 1.
From the Research
Classification of Diastolic Heart Failure
Diastolic heart failure, also known as diastolic dysfunction, can be classified into different stages based on the severity of the condition. The classification is as follows:
- Stage I: Characterized by reduced left ventricular filling in early diastole with normal left ventricular and left atrial pressures and normal compliance 2.
- Stage II or pseudonormalization: Characterized by a normal Doppler echocardiographic transmitral flow pattern because of an opposing increase in left atrial pressures 2.
- Stage III: The final, most severe stage, characterized by severe restrictive diastolic filling with a marked decrease in left ventricular compliance 2.
Diagnosis of Diastolic Heart Failure
The diagnosis of diastolic heart failure requires three conditions:
- Presence of signs or symptoms of heart failure
- Presence of normal or slightly reduced LV ejection fraction (EF > 50%)
- Presence of increased diastolic filling pressure 3. Diastolic heart failure can be diagnosed using various non-invasive and invasive techniques, including:
- 2D- and Doppler-echocardiography
- Color Doppler M-mode
- Doppler tissue imaging
- MR-myocardial tagging
- Radionuclide ventriculography
- Micromanometry
- Angiography
- Conductance method 3.
Characteristics of Diastolic Heart Failure
Diastolic heart failure is associated with a lower annual mortality rate of approximately 8% as compared to annual mortality of 19% in heart failure with systolic dysfunction 3, 4. The pathophysiology of diastolic dysfunction includes delayed relaxation, impaired LV filling and/or increased stiffness, resulting in an upward displacement of the diastolic pressure-volume relationship with increased end-diastolic, left atrial and pulmo-capillary wedge pressure leading to symptoms of pulmonary congestion 3. Diastolic heart failure is an important clinical disorder mainly seen in elderly patients with hypertensive heart disease 3, 4, 5.