Should a patient with diastolic heart failure (DHF) and a history of hypertension, diabetes, or cardiovascular disease be evaluated for chronic kidney disease (CKD)?

Should Patients with Diastolic Heart Failure Be Evaluated for Chronic Kidney Disease?

Yes, all patients with diastolic heart failure must be evaluated for chronic kidney disease, as CKD is present in approximately two-thirds of hospitalized heart failure patients and significantly increases mortality risk—particularly in diastolic heart failure where CKD-associated mortality is 71% higher compared to only 19% higher in systolic heart failure. 1

Why This Evaluation Is Critical

The relationship between diastolic heart failure (heart failure with preserved ejection fraction) and CKD is bidirectional and particularly lethal. Patients with diastolic heart failure and CKD experience 371 extra deaths per 10,000 person-years compared to those without CKD, which is substantially higher than the 214 extra deaths seen in systolic heart failure patients with CKD. 1 This graded association worsens as ejection fraction increases—patients with LVEF >55% and CKD have a hazard ratio of 2.33 for mortality, compared to only 1.15 for those with LVEF <35%. 1

Mandatory Screening Components

All patients with diastolic heart failure require measurement of serum creatinine, calculation of eGFR, and urine albumin-to-creatinine ratio at baseline. 2 This screening should occur regardless of whether traditional CKD risk factors are present, as the prevalence of CKD in heart failure is extraordinarily high—affecting 64.7% of hospitalized heart failure patients (43.9% with moderate CKD, 14.2% with severe CKD, and 6.6% with kidney failure). 3

The specific laboratory evaluation must include:

• Complete metabolic panel with serum creatinine 2
• Calculated eGFR using CKD-EPI equation 2
• Urine albumin-to-creatinine ratio (abnormal if >30 mg/g) 2
• Serum potassium concentration 4
• 12-lead ECG to assess for left ventricular hypertrophy and arrhythmias 5, 2

Clinical Implications of Co-Existing Conditions

The presence of CKD fundamentally changes heart failure management, as patients with both conditions have significantly higher in-hospital mortality rates and require closer monitoring during medication titration. 3 Despite this increased risk, patients with moderate to severe CKD often receive suboptimal guideline-directed medical therapy, with lower use of ACE inhibitors/ARBs and poorer blood pressure control. 3

KDOQI guidelines explicitly state that the level of care for heart failure offered to people with CKD should be the same as offered to those without CKD, and any escalation in therapy or clinical deterioration should prompt monitoring of eGFR and serum potassium. 4 This is particularly important because cardiac biomarkers like BNP/NT-proBNP and troponins must be interpreted with caution in patients with eGFR <60 mL/min/1.73 m², as these markers are inversely associated with GFR level. 4

Staging and Risk Stratification

Once CKD is identified, staging must use both eGFR and albuminuria categories to determine prognosis and guide treatment intensity. 2 The China Kidney Disease Network data demonstrates that among hospitalized CKD patients, heart failure is the second most common cardiovascular disease (18.28%), and patients with diabetes-related kidney disease or hypertensive nephropathy have the highest percentage of cardiovascular disease. 4

Patients with diastolic heart failure should be evaluated for CKD using echocardiographic testing at dialysis initiation (once dry weight is achieved, ideally within 1-3 months) and at 3-yearly intervals thereafter. 4 The E/e' ratio derived from tissue Doppler imaging has prognostic value for cardiovascular morbidity and all-cause mortality in CKD patients, with increased E/e' ratio correlating with both mortality (p=0.048) and cardiovascular events (p=0.045). 6

Treatment Modifications Based on CKD Status

**When CKD is present with diastolic heart failure, blood pressure targets should be <130/80 mmHg in all patients regardless of age, as this reduces cardiovascular mortality and slows kidney disease progression.** 5, 7 For patients with eGFR >30 mL/min/1.73 m², systolic BP of 120-129 mmHg should be targeted if tolerated. 5

ACE inhibitors or ARBs should be initiated as first-line therapy for all patients with CKD stage 3 or higher, or stage 1-2 with albuminuria ≥300 mg/d. 5, 2, 7 Serum creatinine and potassium must be monitored within 1-2 weeks of initiating or titrating these medications. 5, 2, 7 Therapy should be continued unless creatinine rises >30% within 4 weeks. 2

Nephrology Referral Criteria

Referral to nephrology is mandatory when eGFR <30 mL/min/1.73 m² (Stage 4), or earlier if there is uncertainty about CKD etiology, rapidly progressive kidney disease (>30% decline in eGFR within 4 weeks), albuminuria ≥300 mg/g despite treatment, or resistant hypertension. 2, 7 Early referral at Stage 4 reduces cost, improves quality of care, and delays dialysis. 2

Common Pitfalls to Avoid

Do not discontinue ACE inhibitor/ARB for modest creatinine elevation (<30% increase) as cardiovascular benefits outweigh this expected hemodynamic effect. 7 The guideline emphasizes increased vigilance for hyperkalemia and acute kidney injury associated with dual blockade of the renin-angiotensin-aldosterone system. 4

Do not assume that normal baseline creatinine excludes CKD—albuminuria may be present with preserved eGFR, and patients with diastolic heart failure are at particularly high risk. 1 The graded association between CKD-related deaths and LVEF demonstrates that higher ejection fractions paradoxically carry greater CKD-associated mortality risk. 1

Interpret BNP/NT-proBNP levels with caution in patients with eGFR <60 mL/min/1.73 m², as these markers are inversely associated with GFR and may be elevated due to decreased filtration rather than exclusively cardiac damage. 4 However, BNP levels remain strongly associated with left ventricular hypertrophy and dysfunction even in CKD populations. 4