In an older adult with chronic diastolic heart failure, atrial fibrillation with a ventricular pacemaker, anemia treated with ferrous sulfate, obesity, recent 2‑lb weight gain, who experienced two brief episodes of sharp left‑sided chest pain with dyspnea on exertion when beginning to walk, and whose ECG shows a ventricular‑paced rhythm at 69 bpm with blood pressure 126/76 mmHg and heart rate 70 bpm, what is the appropriate immediate evaluation and management?

Immediate Evaluation and Management

This patient requires urgent evaluation for acute coronary syndrome (ACS) given the new-onset chest pain with dyspnea on exertion, despite the paced rhythm and relatively stable vital signs. The combination of diastolic heart failure, atrial fibrillation, anemia, and obesity creates a complex clinical picture where multiple pathologies may be contributing, but acute ischemia must be excluded first.

Immediate Diagnostic Workup

Cardiac Biomarkers and ECG Analysis

• Obtain serial troponins immediately (baseline, 3 hours, and 6 hours if initial negative) to rule out myocardial infarction, as the ventricular-paced rhythm obscures ST-segment analysis and makes ECG interpretation for ischemia unreliable 1
• The paced rhythm at 69 bpm prevents standard ECG diagnosis of ischemia; troponins are your only reliable marker for acute myocardial injury in this setting 1

Volume Status Assessment

• Perform focused physical examination specifically checking for jugular venous distension, hepatojugular reflux, peripheral edema (ankles/sacrum), pulmonary rales, and S3 gallop to assess for acute decompensation 1
• The 2-pound weight gain over 6 months is minimal and does not suggest acute volume overload, but acute decompensation can occur without significant weight change in diastolic heart failure 1
• Obtain chest X-ray to evaluate for pulmonary congestion, pleural effusions, and cardiomegaly 1
• Measure BNP or NT-proBNP to help differentiate cardiac from non-cardiac dyspnea; however, interpret cautiously as levels can be elevated in atrial fibrillation and chronic heart failure without acute decompensation 1

Anemia Evaluation

• Check complete blood count, iron studies (serum iron, TIBC, ferritin), and reticulocyte count to assess adequacy of anemia treatment and rule out acute blood loss 2, 3
• Anemia worsens heart failure through increased cardiac workload (tachycardia, increased stroke volume) and can cause renal hypoperfusion, creating a cardio-renal-anemia syndrome that perpetuates heart failure progression 2
• Target hemoglobin should be >12 g/dL in heart failure patients, as anemia is associated with worse outcomes and more rapid deterioration in cardiac and renal function 2, 3

Renal Function Monitoring

• Obtain basic metabolic panel (creatinine, eGFR, electrolytes including potassium and magnesium) as chronic kidney insufficiency is present in approximately 50% of heart failure patients and contributes to anemia 2

Immediate Management Strategy

If ACS is Ruled Out: Optimize Diastolic Heart Failure Management

The primary therapeutic targets in diastolic heart failure are blood pressure control, heart rate control, volume management, and treatment of myocardial ischemia 1, 4

Blood Pressure Optimization

• Target blood pressure <130/80 mmHg (current 126/76 mmHg is acceptable but may need further reduction if symptomatic) 1, 5
• Continue or optimize ACE inhibitor therapy as first-line to reduce mortality and improve ventricular relaxation through regression of hypertrophy 1, 5
• If ACE inhibitor is not tolerated, substitute with ARB (candesartan has evidence in HFpEF) or hydralazine-nitrate combination 1, 5

Heart Rate and Rhythm Control in Atrial Fibrillation

• Beta-blockers are the preferred first-line agent for rate control in heart failure with atrial fibrillation because they control rate during both rest and exercise, reduce mortality, and improve diastolic filling time by prolonging diastole 1, 6
• Start at extremely low doses and titrate gradually over 1-2 weeks, monitoring for hypotension, bradycardia, and worsening heart failure 6
• Target ventricular rate of 60-100 bpm at rest and <110 bpm during moderate exercise 6
• The current paced rate of 69 bpm is appropriate at rest, but assess rate response during ambulation with 6-minute walk test or ambulatory monitoring 6
• Avoid non-dihydropyridine calcium channel blockers (diltiazem, verapamil) as they have negative inotropic effects that worsen heart failure 6
• Consider restoration of sinus rhythm as patients with diastolic dysfunction are particularly sensitive to loss of atrial kick, which contributes significantly to ventricular filling 1

Volume Management

• Use loop diuretics cautiously and only for symptomatic fluid overload, as excessive preload reduction can paradoxically reduce stroke volume and cardiac output in diastolic dysfunction 1, 5
• The minimal weight gain and current blood pressure suggest this patient is not significantly volume overloaded 1
• Target euvolemia without causing prerenal azotemia 5

Anemia Correction

• Optimize iron supplementation and consider switching from oral ferrous sulfate to intravenous iron if iron studies show deficiency despite oral therapy, as IV iron improves symptoms, cardiac function, and reduces hospitalizations in heart failure 2, 3
• Consider adding erythropoietin-stimulating agents if hemoglobin remains <12 g/dL despite adequate iron stores, though await results of ongoing trials (RED-HF) for definitive guidance 3
• Correcting anemia reduces cardiac workload and may slow progression of both heart failure and renal dysfunction 2

Monitoring Protocol

• Schedule follow-up within 7-10 days to assess medication tolerance, symptom improvement, and laboratory parameters (renal function, electrolytes, CBC) 5
• Perform ambulatory ECG monitoring or exercise testing to assess rate control during exertion 6
• Check orthostatic vital signs at each visit, as elderly patients with stiff arteries are prone to exaggerated postural hypotension 6

Critical Pitfalls to Avoid

• Do not dismiss chest pain in a paced rhythm—troponins are essential as ECG is unreliable for ischemia detection 1
• Do not over-diurese—diastolic dysfunction requires adequate preload; excessive diuresis worsens symptoms 1, 5
• Do not use calcium channel blockers for rate control—they worsen heart failure outcomes and increase hospitalizations by 38% 5, 6
• Do not ignore anemia—it is not just a marker but likely a mediator of heart failure progression through the cardio-renal-anemia syndrome 2, 3
• Do not abruptly discontinue beta-blockers even if temporary worsening occurs; instead adjust diuretics or temporarily reduce dose 6