Diastolic heart failure, also known as heart failure with preserved ejection fraction (HFpEF), is a condition in which the heart's ability to relax and fill with blood is impaired, despite normal pumping function. While less recognized than systolic heart failure, diastolic dysfunction is increasingly common and contributes to significant morbidity and mortality—especially among the elderly.
To simplify the complex causes behind diastolic heart failure, the mnemonic “PARIAH” is often used in medical education. In this article, we break down each component of "PARIAH," provide real-world context, explore diagnostic and management strategies, and uncover ways to improve patient outcomes.
Pericardial Disease – The External Constraint
The pericardium is the sac-like structure that surrounds the heart. Any disease affecting this layer, such as constrictive pericarditis or pericardial effusion, can physically restrict the heart's ability to fill during diastole. This restriction mimics the effects of intrinsic myocardial stiffness, causing symptoms such as breathlessness, fatigue, and peripheral edema.
Constrictive pericarditis, often a result of previous infections, surgeries, or radiation therapy, leads to a rigid pericardium that limits expansion. Diagnosis may involve imaging like echocardiography or MRI, and treatment can range from anti-inflammatory medications to pericardiectomy (surgical removal of the pericardium).
Age – The Unchangeable Factor
Aging is a natural risk factor for diastolic dysfunction. With advancing age, myocardial tissue undergoes fibrosis, loss of elasticity, and cellular senescence. This structural transformation makes the heart less compliant, meaning it can no longer fill efficiently during diastole even if the ejection fraction remains normal.
Additionally, elderly individuals often present with comorbidities such as hypertension, diabetes, and atrial fibrillation, which compound the decline in diastolic function. Lifestyle interventions, early detection, and appropriate pharmacologic support become essential to maintain quality of life in aging patients.
Restrictive Cardiomyopathy – The Rigid Myocardium
Restrictive cardiomyopathy (RCM) is a rare but serious cause of diastolic heart failure. It is characterized by stiff ventricular walls that resist filling. Despite a normal thickness and preserved systolic function, these hearts cannot accommodate blood during relaxation.
RCM may be idiopathic or secondary to conditions like amyloidosis, sarcoidosis, or hemochromatosis, where abnormal protein or iron deposits infiltrate the myocardium. These deposits cause inflammation and fibrosis, drastically reducing compliance.
Diagnosis often includes endomyocardial biopsy and imaging modalities like cardiac MRI. While there is no cure for RCM, management focuses on treating the underlying cause and relieving symptoms with diuretics and careful volume control.
Ischemic Heart Disease – The Energy Starvation
Ischemic heart disease (IHD) occurs when coronary arteries become narrowed or blocked, reducing blood flow to the heart muscle. Chronic ischemia affects not only contraction but also relaxation. Post-infarction scarring, hibernating myocardium, and residual ischemia can all contribute to impaired diastolic function.
Even in the absence of a large infarction, repeated small ischemic events can stiffen the myocardium over time. In patients with preserved ejection fraction but significant coronary artery disease, symptoms of heart failure often indicate diastolic dysfunction.
Treatment focuses on restoring coronary perfusion via medications, angioplasty, or bypass surgery, alongside long-term management with beta-blockers, statins, and lifestyle changes.
Aortic Stenosis – The Pressure Overload
Aortic stenosis (AS) is a condition in which the aortic valve becomes narrowed, forcing the heart to pump harder to eject blood. Over time, this pressure overload causes the left ventricle to hypertrophy, leading to thickened walls that resist filling.
While AS typically presents with exertional dyspnea, angina, or syncope, its impact on diastolic function is profound. Left untreated, this mechanical barrier progresses to heart failure, even if systolic performance is initially preserved.
Echocardiography is key to diagnosing AS, and definitive treatment involves valve replacement—either surgically or via transcatheter aortic valve implantation (TAVI), especially in elderly patients.
Hypertension – The Silent Contributor
Chronic hypertension remains the most prevalent cause of diastolic heart failure worldwide. High blood pressure overworks the heart, causing left ventricular hypertrophy (LVH) and arterial stiffening. Over time, the heart becomes less flexible and unable to relax properly during diastole.
Patients with hypertensive heart disease may experience nocturnal dyspnea, orthopnea, or exercise intolerance. Early management of blood pressure using ACE inhibitors, ARBs, calcium channel blockers, and diuretics is critical to preventing the transition from hypertrophy to heart failure.
Additionally, lifestyle modifications like reducing salt intake, weight loss, and regular exercise play a powerful role in controlling hypertension and protecting diastolic function.
Table: “PARIAH” Mnemonic Breakdown
| Mnemonic Letter | Cause | Description |
|---|---|---|
| P | Pericardial Disease | Constriction or effusion restricts heart filling |
| A | Age | Aging stiffens the myocardium |
| R | Restrictive Cardiomyopathy | Fibrosis from infiltrative diseases |
| I | Ischemic Heart Disease | Chronic or post-infarction stiffness |
| A | Aortic Stenosis | Pressure overload induces hypertrophy |
| H | Hypertension | Commonest cause via LVH |
Frequently Asked Questions (FAQs)
Q1: What is the difference between systolic and diastolic heart failure?
Systolic heart failure occurs when the heart can’t pump efficiently, while diastolic heart failure means the heart can’t fill properly despite normal pumping strength.
Q2: Is diastolic heart failure reversible?
While it’s not entirely reversible, early diagnosis and management of underlying causes (like hypertension and valve disease) can stabilize or slow progression.
Q3: Can young people get diastolic heart failure?
It is less common but possible, especially with congenital conditions, autoimmune diseases, or secondary causes like pericarditis and infiltrative cardiomyopathies.
Q4: What lifestyle changes help with diastolic heart failure?
Managing blood pressure, reducing sodium intake, avoiding alcohol, exercising moderately, and addressing comorbidities are key lifestyle strategies.
Q5: How is diastolic heart failure diagnosed?
Diagnosis includes echocardiography, Doppler studies, ECG, and sometimes cardiac MRI to assess ventricular filling, wall stiffness, and structural integrity.
Q6: What medications are used for diastolic heart failure?
While no drugs specifically target diastolic failure, diuretics, beta-blockers, ACE inhibitors, ARBs, and mineralocorticoid receptor antagonists are often used to manage symptoms and comorbidities.
