Key points
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Hemodynamic instability or even collapse, hypotension, and arrhythmias caused by a large right/left atrial or atrioventricular valve mass, limiting venous return and obstruction/restriction of intracardiac blood flow.
(Anesthetic implications: Careful positioning of patient, preparation for major volume replacement, large bore IV and central venous access, vasoactive drug ready for immediate use, surgeon present in operating room during anesthesia induction, cardiopulmonary bypass primed and prepared for immediate use)
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Possibility of myocardial depression (intramural mass), reduction in coronary perfusion pressure, and systemic vascular resistance (SVR).
(Anesthetic implications: Minimize dose of preoperative sedatives, titration of anesthesia induction drugs)
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Mass particle embolization.
(Anesthetic implications: IOTEE for intraoperative monitoring, placing central venous catheter at femoral site is preferred)
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Atrial fibrillation or ventricular arrhythmias are not uncommon.
(Anesthetic implications: Placing defibrillator pads before anesthesia induction for instantaneous cardioversion/defibrillation as needed)
Anesthetic management for resection of cardiac mass (including tumor, large clot, or vegetation) begins with an inclusive review of the preoperative imaging modalities by the cardiac anesthesiologist . This evidence will enable the anesthesiologist to anticipate the possible intraoperative pathophysiologic considerations of the mass, based on size, mobility, and location . For example, if a large mass (tumor or clot) is present in the right atrium (RA) , restriction or obstruction of venous return could potentially cause severe hypotension or arrhythmias ( Fig. 26.1 ). The anesthetic implications in the approach to such an event should include careful positioning of the patient on the operating table to reduce the risk of impaired venous return .
The anesthesiologist also needs to be ready for rapid volume replacement and resuscitation and immediate administration of a vasopressor if the patient becomes hemodynamically unstable due to decreased venous return or blood flow obstruction because of a large mass effect in the RA restricting blood flow through the tricuspid valve . Because of the probability of hemodynamic collapse in such situations, the surgeon should be present in the operating room and ready for cardiopulmonary bypass (CPB) at all times, including during anesthesia induction. The anesthesiologist should minimize the use of sedative drugs in the preoperative period, and the dosage of induction agents must be titrated and administered cautiously in such patients. The aim of this practice is to avoid myocardial depression and to maintain adequate systemic vascular resistance (SVR) and coronary perfusion pressure. Maintaining adequate right ventricular filling pressure and volume and maintaining normal sinus rhythm reduces hemodynamic instability during anesthesia induction .
If the patient presents with a large intracardiac mass located in the atria or the tricuspid (or mitral) valves ( Fig. 26.2 ), although administration of inotropes may be necessary to increase myocardial contractility, it is crucial to know that enhanced contractility can increase outflow tract obstruction (mimic valve stenosis) and may cause a dramatic decrease in intracardiac blood flow ( Fig. 26.3 ). In addition, chronic mass effects could result in valvular stenosis or incompetence. Because of possible hepatic metastasis ( Fig. 26.4 ), the anesthesiologist must assess liver function tests preoperatively in patients presenting with a malignant tumor so that drug dosage may be adjusted if indicated ( Supplementary Videos 26.1–26.4 ).
In right side cardiac masses, particle embolization can lead to acute pulmonary hypertension with or without hemodynamic instability or even collapse . The anesthesiologist might consider placement of a central venous catheter at the femoral vein instead of the internal jugular (or subclavian) vein, as a safer alternative to avoid atrial fibrillation or contact with the right side cardiac mass (especially fresh clots). Defibrillation pads are suggested to be placed before anesthesia induction so that the patient can be immediately cardioverted-defibrillated if needed. Atrioventricular block and ventricular arrhythmias are not uncommon in the perioperative period, particularly in patients who present with intramyocardial or intracavity masses that infiltrate to or cause inflammation of conduction fibers . Arrhythmias can occur acutely after surgical resection, and may require a permanent pacemaker . During anesthesia we must ensure that an adequate anesthesia depth is provided, especially in stimulating events such as laryngoscopy, surgical incision, and sternotomy, to prevent an acute hypertension or rise in RA pressure and atrial dysrhythmia .
