Acute cor pulmonale in patients with acute respiratory distress syndrome: A comprehensive review

Table 1 Definitions and prevalence of acute respiratory distress syndrome -related acute cor pulmonale

Ref.	Definition	Test	Prevalence
Vieillard-Baron et al[5] (2001)	Ratio of right ventricular end-diastolic area to left ventricular end-diastolic area in the long axis > 0.6 associated with septal dyskinesia in the short axis	TEE	19/75 (25%)
Jardin et al[4] (2007)	Ratio of right ventricular end-diastolic area to left ventricular end-diastolic area in the long axis > 0.6 associated with septal dyskinesia in the short axis	TEE	101/352 (29%)
Vieillard-Baron et al[6] (2007)	Ratio of right ventricular end-diastolic area to left ventricular end-diastolic area in the long axis > 0.6 associated with septal dyskinesia in the short axis	TEE	21/42 (50%)
Fichet et al[9] (2012)	Right ventricular dilatation was defined by a right ventricular end-diastolic area to left ventricular end-diastolic area ratio > 0.6 and reported as severe when ratio was ≥ 1 (apical four-chamber view). ACP was defined by right ventricular dilatation associated with septal dyskinesia observed in the short-axis view	TTE	ACP: 4/50 (8%); Severe ACP: 4/50 (8%)
Boissier et al[2] (2013)	Ratio of right ventricular end-diastolic area to left ventricular end-diastolic area in the long axis > 0.6 associated with septal dyskinesia in the short axis	TEE	49/226 (22%)
Lhéritier et al[7] (2013)	Association of right ventricular dilatation inthe long-axis view of the heart (ratio of right ventricular end-diastolic area to left ventricular end-diastolic area > 0.6) and a visually identified systolic paradoxical ventricular septal motion in the short-axis view of the heart	TEE	45/200 (23%)
Mekontso-Dessap et al[14] (2015)	Septal dyskinesia (in the short axis) with a dilated right ventricle (end-diastolic right/left ventricle area ratio > 0.6 in the long axis). Severe ACP defined as septal dyskinesia (in the short axis) with a dilated right ventricle (end-diastolic right/left ventricle area ratio ≥ 1 in the long axis)	TEE	ACP: 164/752 (22%); Severe ACP: 54/752 (7%)
Legras et al[8] (2015)	Association of right ventricular dilatation inthe long-axis view of the heart (ratio of right ventricular end-diastolic area to left ventricular end-diastolic area > 0.6) and a visually identified systolic paradoxical ventricular septal motion in the short-axis view of the heart	TEE	36/195 (18%)
Cecchini et al[10] (2016)	Dilated right ventricle (end-diastolic right ventricle/left ventricle area ratio > 0.6) associated with septal dyskinesia on the short-axis view	TEE or TTE	88/362 (24%)
See et al[1] (2017)	Severe ACP defined as right-to-left ventricular size (area) ratio ≥ 1 in end diastole at the papillary muscle level and interventricular septal straightening/paradoxical motion using the parasternal short axis view. NB. Apical four-chamber view was used as a secondary safeguard against false ACP determination, which did not occur	TTE	Only severe ACP reported: 66/234 (28%)

ACP: Acute cor pulmonale; ARDS: Acute respiratory distress syndrome; TEE: Transesophageal echocardiography; TTE: Transthoracic echocardiography.

Table 2 Management options for acute respiratory distress syndrome-related acute cor pulmonale

Management option	Details	Best supporting evidence
Ventilator adjustment	Limit end-inspiratory plateau pressure to 30 cmH2O. Target a tidal volume of 6-9 mL/kg. Positive end-expiratory pressure selected to improve oxygenation without requiring specific hemodynamic support, except for blood volume expansion	Observational study[5]
	Aim for partial pressure of carbon dioxide < 60 mmHg	Observational study[7]
	Aim for partial pressure of carbon dioxide < 48 mmHg	Observational study[14]
	Aim for plateau pressure < 27 cmH2O	Observational study[4]
	Aim for driving pressure < 17 cmH2O	Observational study[2]
Prone positioning	Ventilation in the prone position, especially for patients with refractory severe hypoxemia (P/F ratio < 100 mmHg)	Observational study[5,6,29]
Fluid balance optimization	Stop volume expansion	Expert opinion[22]
	Consider diuresis or fluid removal using hemofiltration	Expert opinion[28]
Pharmacotherapy	Pulmonary vasodilation using inhaled nitric oxide	Expert opinion[16]
	Pulmonary vasodilation using levosimendan	Pilot trial[23]
	Vasopressors to restore systemic blood pressure and to avoid right ventricular ischemia	Expert opinion[28]

ACP: Acute cor pulmonale; ARDS: Acute respiratory distress syndrome; P/F = Arterial partial pressure of oxygen/inspired oxygen fraction.