A Viewpoint on the Role of Right Heart in General Anesthesia

Dear Editor,

I read with interest the case series by Shivpriya et al.^[1] published in your esteemed journal. The series deserves appreciation for focusing on a clinically relevant, physiologically vulnerable group of patients with elevated body mass index (BMI) and chronic airflow limitation and for highlighting the tricuspid annular plane systolic excursion–pulmonary artery (PA) systolic pressure (TAPSE–PASP) relationship as a practical echocardiographic surrogate for right ventricular (RV)–PA interaction,^[1] in this specific perioperative setting. The additional merit of the study lies in linking pre-operative right heart physiology to peri-induction hypotension, thereby generating a clinically relevant hypothesis for perioperative risk stratification. At the same time, the descriptive nature of a small case series, lack of a comparator group, and possible influence of intraoperative confounders limit causal interpretation.

While the authors define obesity with BMI more than 30 kg/m² as per the World Health Organization criteria, BMI alone may not adequately reflect the extent of pulmonary vascular and cardiopulmonary involvement.^[1] A more physiological and personalized informative dimension is captured by the STOP-BANG score, serving as a surrogate for the patient-specific risk of obstructive sleep apnea (OSA).^[2,3] This distinction is relevant in the Asian population, where OSA and its cardiopulmonary sequelae often manifest at lower BMI thresholds, and where craniofacial and anthropometric factors contribute to sleep-disordered breathing.^[2] These patients, despite modest BMI elevation, may exhibit an elevated STOP-BANG score with a cumulative burden of intermittent hypoxia, sympathetic activation, pulmonary vascular remodeling, and increased PA pressures.^[1,2]

The authors included patients with moderate chronic obstructive pulmonary disease (COPD), using internationally accepted Global Initiative for Chronic Obstructive Lung Disease classification criteria.^[1] The patients with moderate disease are susceptible to dynamic changes in lung mechanics during anesthesia, particularly bronchospasm and expiratory flow limitation.^[4] Bronchospasm and mucus impaction increase airway resistance, leading to expiratory flow limitation and dynamic hyperinflation, with a consequent rise in intrathoracic pressure and reduction in venous return and RV preload.^[4] Perioperative bronchospasm is a recognized complication in patients with COPD undergoing non-cardiac surgery, and such dynamic airway events may have influenced the RV loading conditions and peri-induction hemodynamics in the patients involved in the index case series.^[1,4]

In this context, it would be pertinent to know whether any episodes of intraoperative bronchospasm or increased airway pressures were observed in this cohort, as these factors could potentially confound the relationship between pre-operative RV-PA coupling and intraoperative hypotension.^[1] The TAPSE/PASP offers a practical, bedside means of evaluating RV interaction with the pulmonary circulation. However, other echocardiographic indices derived from RV outflow tract Doppler analysis have been described in the literature, particularly in sepsis.^[5] It would be interesting to know about the authors’ experience with the same.^[1,5]

The perioperative literature evaluating TAPSE/PASP in obese COPD patients remains limited. While Gulasti et al.’s^[6] study established the TAPSE/PASP ratio as a broad predictive tool for a healthy population, Shivpriya et al.^[1] investigated its utility in high-risk patients predisposed to right heart stress. In my view, this report is valuable as an important early signal that perioperative assessment of RV-PA coupling using TAPSE-PASP may improve risk stratification in selected high-risk patients, although larger prospective studies are needed before broader conclusions can be drawn. I commend the authors for addressing this challenging topic and hope these comments contribute constructively to the ongoing dialog in this field.