Patient with paroxysmal nocturnal dyspnea, resting tachycardia >100 bpm, intermittent systolic hypotension <90 mm Hg, fatigue, exercise intolerance, and headaches when hypotensive—what is the most likely diagnosis and recommended acute management?

Acute Decompensated Heart Failure with Hypotension

This patient most likely has acute decompensated heart failure (ADHF) and requires urgent hospitalization with immediate initiation of intravenous diuretics, continuous hemodynamic monitoring, and echocardiographic assessment to guide management. 1

Most Likely Diagnosis

Acute decompensated heart failure is the primary diagnosis based on the constellation of paroxysmal nocturnal dyspnea, persistent tachycardia >100 bpm, intermittent systolic hypotension <90 mmHg, generalized fatigue, and exercise intolerance. 1

• Paroxysmal nocturnal dyspnea is a classic symptom of elevated pulmonary venous pressure and pulmonary congestion due to left-sided cardiac disease, occurring in patients with heart failure. 1
• The combination of orthopnea and paroxysmal nocturnal dyspnea strongly suggests elevated pulmonary venous pressure rather than pulmonary arterial hypertension alone. 1
• Persistent tachycardia >100 bpm at rest with blood pressure fluctuations indicates hemodynamic instability and inadequate cardiac compensation. 1
• Fatigue, exercise intolerance, and symptoms of reduced cardiac output are common presenting features of heart failure. 1

Critical Triage Criteria

This patient meets criteria for intensive care unit or coronary care unit admission based on hemodynamic instability. 1

• Systolic blood pressure <90 mmHg is an explicit criterion for ICU/CCU referral in acute heart failure. 1
• Heart rate >100 bpm (specifically >120 bpm in some guidelines, but persistent tachycardia >100 throughout the day warrants close monitoring) indicates hemodynamic compromise. 1
• Symptoms of hypoperfusion (headaches with hypotension, fatigue, exercise intolerance) suggest inadequate end-organ perfusion. 1

Immediate Acute Management

Initial Monitoring and Assessment

Continuous non-invasive monitoring must be initiated immediately including pulse oximetry (target SpO2 >90%), blood pressure, heart rate/rhythm via ECG, respiratory rate, and urine output. 1

• Oxygen therapy should be administered if SpO2 <90% or based on clinical judgment if respiratory distress is present. 1
• Obtain 12-lead ECG immediately to assess for ischemia, arrhythmias, or chamber enlargement. 1
• Urgent transthoracic echocardiography is essential to evaluate left and right ventricular function, valvular disease, pericardial pathology, and estimate pulmonary artery pressures. 1

Laboratory Evaluation

Immediate laboratory testing should include: 1

• B-type natriuretic peptide (BNP) or NT-proBNP to confirm heart failure (BNP >100 pg/mL or NT-proBNP >125 pg/mL supports diagnosis). 2
• Electrolytes, renal function (creatinine, BUN), and glucose to assess for metabolic derangements and renal dysfunction. 1
• Cardiac troponin to evaluate for acute coronary syndrome as a precipitant. 1
• Complete blood count to assess for anemia. 1

Pharmacologic Management Strategy

The approach to pharmacologic therapy depends critically on blood pressure at presentation: 1, 3

If Systolic BP >90 mmHg (Current State: 109/75 mmHg):

• Initiate intravenous loop diuretics (e.g., furosemide 40-60 mg IV bolus, repeat as needed based on diuretic response). 1
• Target urine output >100 mL/hour in first 2 hours as adequate response. 1
• Consider vasodilators (e.g., nitroglycerin starting at 10 μg/min IV, titrated every 10 minutes based on blood pressure response) if systolic BP remains >110 mmHg and patient has signs of congestion. 1
• Monitor closely for hypotension during diuretic and vasodilator therapy. 1, 3

If Systolic BP <90 mmHg (Intermittent State):

• Hold or reduce vasodilators and diuretics temporarily until blood pressure stabilizes. 1, 3
• Consider inotropic support with dobutamine (start at 2.5 μg/kg/min IV, titrate every 15 minutes based on response, maximum usually 20 μg/kg/min) if signs of hypoperfusion persist despite adequate filling pressures. 1
• Dopamine at low doses (2.5 μg/kg/min) may be considered if inadequate diuresis despite adequate filling pressure, though higher doses are not recommended solely for diuresis. 1
• Avoid further reduction of blood pressure-lowering medications that have Class I indication for heart failure (ACE inhibitors, beta-blockers, ARBs) unless hypotension is severe and persistent. 3

Critical Pitfall: Managing Hypotension in Heart Failure

Do not reflexively discontinue guideline-directed medical therapy for heart failure due to asymptomatic or mild hypotension. 3

• In non-severe asymptomatic hypotension, maintain current doses of drugs with Class I indication (ACE inhibitors/ARBs, beta-blockers, aldosterone antagonists). 3
• First decrease blood pressure-reducing drugs NOT indicated in heart failure (e.g., calcium channel blockers, alpha-blockers). 3
• Reduce loop diuretic dose if no signs of congestion present. 3
• Seek heart failure specialist consultation before stopping or decreasing Class I indicated medications. 3

Differential Diagnoses to Exclude

Pulmonary Arterial Hypertension

While paroxysmal nocturnal dyspnea can occur with pulmonary hypertension, the presence of orthopnea and PND more strongly suggests left-sided heart disease rather than isolated pulmonary arterial hypertension. 1

• Pulmonary arterial hypertension typically presents with exertional dyspnea (60% of cases), fatigue, and syncope, but orthopnea and PND specifically suggest pulmonary venous congestion. 1
• Echocardiography will help differentiate by assessing left ventricular function and estimating pulmonary artery pressures from tricuspid regurgitation jet. 1

Sleep-Disordered Breathing

Sleep apnea may coexist with heart failure and can contribute to paroxysmal nocturnal dyspnea through nocturnal hemodynamic changes. 4

• In patients with acute decompensated heart failure, sleep apnea (measured by respiratory disturbance index) is independently associated with paroxysmal nocturnal dyspnea and overnight worsening hemodynamics. 4
• However, sleep apnea evaluation should occur after stabilization of acute heart failure, not during acute presentation. 1
• Polysomnography is recommended if obstructive sleep apnea is suspected after heart failure stabilization. 1

Acute Coronary Syndrome

Given the persistent tachycardia and symptoms of reduced perfusion, acute coronary syndrome must be excluded. 1

• Cardiac troponin measurement is essential. 1
• ECG should be examined for ischemic changes. 1
• If angina or significant ischemia is present with heart failure, coronary arteriography is indicated (Class I recommendation). 5

Monitoring During Hospitalization

Daily monitoring should include: 1

• Daily weight measurement and accurate fluid balance chart. 1
• Daily renal function (creatinine, BUN) and electrolytes. 1
• Continuous pulse, respiratory rate, and blood pressure monitoring until stabilized. 1
• Pre-discharge natriuretic peptide measurement for post-discharge planning (falling levels predict better outcomes). 1

Criteria for Hemodynamic Stability and Discharge

Patient is medically fit for discharge when: 1

• Hemodynamically stable and euvolemic for at least 24 hours before discharge. 1
• Established on evidence-based oral medication with stable renal function. 1
• Provided with tailored education about self-care. 1
• Follow-up arranged with general practitioner within 1 week and cardiology within 2 weeks. 1