Pre- and perioperative considerations
Indications for valve surgery in CaHD patients are outlined in
guidelines (11Davar J, Connolly HM, Caplin ME et al. Diagnosing
and Managing Carcinoid Heart Disease in Patients With Neuroendocrine
Tumors: An Expert Statement. J Am Coll Cardiol. 2017;69(10):1288-1304.)
and include progressive right heart failure with echocardiographical
findings of moderate to severe insufficiency of the right-sided valves.
The TV is always involved in surgical candidates and is usually severely
regurgitant, while the PV is often affected, showing a combination of
stenosis and regurgitation. The decision for valve replacement should be
based on a multidisciplinary evaluation of general operability in
relation to oncological status and cardiac function. Timing of surgery
with preoperative optimization of nutritional status and somatostatin
analog treatment for carcinoid hormonal activity is essential. Studies
indicate that earlier intervention rather than late improves outcomes
(7). Valve surgery always involves tricuspid valve replacement (TVR) and
most often pulmonary valve replacement (PVR). In our experience, the PV
pathology is often underestimated on echocardiography, and a larger
regurgitation may be unmasked by a higher forward flow after TVR, if
leaving the PV untreated. Also, an uncorrected significant pulmonary
regurgitation after TVR may lead to progressive right heart dilatation
and poorer results (22Connolly HM, Schaff HV, Mullany CJ et al.
Carcinoid heart disease: impact of pulmonary valve replacement in
right ventricular function and remodeling.
Circulation. 2002;106(12 Suppl 1):I51-I56.). Thus, a low threshold is
recommended for replacing the PV. The aortic or mitral valves may also
be involved in 10-15% of cases with CaHD. A previous report has shown
that surgery of the left-sided valves is not a factor for worse results
and should be performed concomitantly with right-sided valve surgery if
indicated (5).
A particular risk with CaHD patients is the occurrence of a carcinoid
crisis during surgery. Anesthesia, surgery or drugs may trigger release
of vasoactive hormones, causing potentially life-threatening circulatory
instability with severe hypotension and flushing (33Castillo J,
Silvay G, Weiner M. Anesthetic Management of Patients
With Carcinoid Syndrome and Carcinoid Heart Disease: The Mount Sinai
Algorithm. J Cardiothorac Vasc Anesth. 2018;32(2):1023-1031.).
Routine therapy to counter this complication is infusion of short-acting
octreotide, started prior to surgery (in some cases 24 hours), continued
perioperatively and for several days postoperatively.
Furthermore, intraoperative protection of right ventricular
(RV) function is key. The RV is dilated in most surgical candidates, and
surgery should be performed before significant RV dysfunction develops.
CaHD patients are at increased risk of bleeding during surgery, due to
their oncological status, severe preoperative venous stasis and reduced
liver function. Increased attention to bleeding control is important,
regarding surgical technique, use of autologous blood recovery systems
and optimization of postoperative coagulation using point-of-care
techniques.