From the Guidelines
The RSR pattern in V1-V2 leads is indicative of complete right bundle branch block (RBBB), which is defined by a QRS duration ≥120 ms, rsr', rsR, or rSR pattern in leads V1 or V2, and an S wave of greater duration than the R wave or >40 ms in leads I and V6 in adults, as stated in the 2019 ACC/AHA/HRS guideline 1. The treatment of RBBB should focus on addressing the underlying cause, which may include pulmonary hypertension, congenital heart disease, or chronic lung disease.
- First-line medications typically include diuretics like furosemide 20-40mg daily to reduce fluid overload, and vasodilators such as sildenafil 20mg three times daily or bosentan 62.5mg twice daily if pulmonary arterial hypertension is present, as suggested by the 2019 ACC/AHA/HRS guideline 1.
- Oxygen therapy should be provided if hypoxemia is detected.
- For patients with underlying COPD, bronchodilators like tiotropium 18mcg daily or combination inhalers may be beneficial.
- ACE inhibitors or ARBs may be added if there's concurrent left heart disease. The definition of complete RBBB is further supported by the 2009 AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram, which states that complete RBBB is characterized by a QRS duration greater than or equal to 120 ms in adults, and an rsr, rsR, or rSR pattern in leads V1 or V, with the R or r deflection usually wider than the initial R wave 1. Regular follow-up with serial echocardiography every 3-6 months is essential to monitor progression, as recommended by the 2019 ACC/AHA/HRS guideline 1. The treatment aims to reduce right ventricular pressure overload, prevent right heart failure, and improve symptoms like dyspnea, fatigue, and peripheral edema by addressing the pathophysiological mechanisms causing the increased right ventricular workload.
From the Research
RSR' Pattern in Leads V1-V2
The RSR' pattern in leads V1-V2 can be caused by various conditions, ranging from benign non-pathological variants to severe heart diseases.
- The differential diagnosis of this pattern is crucial to identify the underlying cause and provide appropriate treatment 2.
- An RSR' pattern with a QRS duration of less than 0.12 seconds in the right precordial leads can be due to incomplete right bundle branch block or a normal electrophysiological variant 3.
- Certain ECG features, such as diminution of the S wave depth, inversion of the ratio of the S wave depth to SV1 > SV2, slurring of the downstroke or upstroke of the S wave, and prolongation of the QRS duration, can help distinguish between these two possibilities 3.
Diagnostic Criteria
- New ECG criteria based on the r' wave can accurately identify RSR' patterns in V1-V2 from potential Brugada type 2 patterns in patients with purposely placed high precordial leads 4.
- The presence of right bundle branch block (RBBB) with a QR pattern in V1 on the electrocardiogram (ECG) has a high positive predictive value for diagnosing cardiac arrest caused by high-risk pulmonary embolism 5.
Prognosis
- The RSR' pattern is not associated with an increased risk of cardiovascular disease or all-cause mortality in older adults free of clinical cardiovascular disease 6.
- However, certain conditions, such as Brugada syndrome or arrhythmogenic right ventricular dysplasia, can be life-threatening and require prompt diagnosis and treatment 2.