CHADS₂ Score Calculation
This patient has a CHADS₂ score of 5 points, placing him at very high risk for stroke with an annual stroke rate of approximately 12.5%.
Score Breakdown
The CHADS₂ scoring system assigns points as follows 1:
- C (Congestive Heart Failure): 1 point - Present (high JVP, S3 heart sound, bi-basal crackles indicate acute decompensated heart failure) 1
- H (Hypertension): 1 point - Present (known hypertension, current BP 150/90 mmHg) 1
- A (Age ≥75 years): 0 points - Age not specified as ≥75 years 1
- D (Diabetes Mellitus): 1 point - Present (known diabetic) 1
- S₂ (Prior Stroke/TIA): 2 points - Present (history of stroke) 1
Total CHADS₂ Score: 5 points
Risk Stratification and Clinical Implications
At a CHADS₂ score of 5, this patient faces an adjusted annual stroke rate of 12.5% (95% CI 8.2-17.5%) without anticoagulation 1. This represents very high risk, with only 8 patients needing treatment for one year to prevent one stroke 1.
The score of 5 falls into the highest risk category, where the absolute benefit of anticoagulation substantially outweighs bleeding risk 1. Patients with CHADS₂ scores ≥2 require oral anticoagulation therapy with warfarin (target INR 2.5, range 2.0-3.0) unless contraindicated 1.
Critical Clinical Considerations
The history of prior stroke alone (worth 2 points) automatically places this patient in the high-risk category requiring anticoagulation, regardless of other risk factors 2. Prior stroke or TIA is weighted as 2 points because previous thromboembolism is associated with highly elevated risk of recurrence 3.
The presence of acute heart failure with hemodynamic instability (tachycardia 144/min, hypoxemia 89%, elevated JVP) requires immediate rate control and stabilization before initiating anticoagulation 1. However, the high CHADS₂ score mandates that anticoagulation be initiated once the patient is stabilized 1.
Comparison with CHA₂DS₂-VASc Score
While the CHADS₂ score is 5, the CHA₂DS₂-VASc score would be even higher (at least 6-7 points depending on age and presence of vascular disease), as it includes additional risk factors such as vascular disease and sex category 1, 3. The CHA₂DS₂-VASc score demonstrates superior sensitivity for risk stratification, particularly with a c-statistic of 0.606-0.67 versus 0.561 for CHADS₂ 3.