J. Andreas Hoschtitzky

Which is the best tissue valve used in the pulmonary position, late after previous repair of tetralogy of Fallot?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: which is the best tissue valve for use in the pulmonary position, late after previous repair of tetralogy of Fallot? Altogether 141 papers were found using the reported search, of which 13 represented the best evidence to answer the clinical question. In addition to this, 1 paper was found by searching the reference lists of the relevant papers. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude from the best evidence available that homograft valves function well in the pulmonary position late after Tetralogy of Fallot (TOF) repair. This is particularly evident in the larger studies where the patients were only treated with homografts. It has been suggested that Homografts are better than xenografts and this has not been statistically shown. Two articles have suggested that xenografts outperform homografts however, in both studies these results were not statistically significant. Furthermore, early indications suggest that porcine valves may be better than bovine pericardial valves but a better longer term follow-up is certainly required to demonstrate this. It is important to realize also that when comparing the effectiveness of these valves in the pulmonary position, one cannot ignore confounding factors. The most important of these include timing of operation, age of patient, valve size, immunological factors, operative complexity and also postoperative valvular gradients. The timing of these operations has always been an area of great controversy illustrated by varied guidelines. There is no general consensus regarding whether there is even a role of pulmonary valve replacement late after TOF repair. Further weakening any conclusions that may be drawn based on current best evidence is the lack of strong follow-up data (transvalvular gradients and right ventricular (RV) volumetric data). New research is required with comparisons using objective clinical parameters in order to more effectively answer our clinical question.

Is there a role for mechanical valve prostheses in pulmonary valve replacement late after tetralogy of Fallot repair

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: What is the role of mechanical valve prostheses in pulmonary valve replacement late after tetralogy of Fallot (TOF) repair? Altogether more than 30 papers were found using the reported search, of which 9 represented the best evidence to answer the clinical question. In addition to this, two papers were found by searching the reference lists of the relevant papers. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude from the best evidence available that mechanical prosthetic valves do play a role in patients who require pulmonary valve replacement late after repair of TOF. With adequate anticoagulation, they represent a safe alternative to biological valves. Although the literature is very limited, in terms of patient numbers, many of the papers demonstrate an acceptable early mortality rate. There is significant variability in the regimes of anticoagulation in these patients, and the overall reported rate of valvar thrombosis, thromboembolic events and major haemorrhagic complications has also been variable. The overall rate of valvar thrombosis and other thromboembolic events is promising. Thrombotic events were often attributed to poor adherence to the anticoagulation regime. Conversely, 3 papers recorded no thromboembolic events during the follow-up period. Three papers recorded major haemorrhagic events during their follow-up period and concluded that these were a rare outcome. When appropriate anticoagulation is adhered to, mechanical pulmonary prostheses appear to be relatively safe in patients late after repair of TOF. We have also found that the rationale for insertion of mechanical valves in the pulmonary position late after TOF repair varies across centres is still controversial. Furthermore, their use in patients with concomitant pulmonary arterial stenoses may be less advisable as this will prevent future percutaneous interventions of the pulmonary arterial tree. More research is required to accurately compare the haemodynamic properties of mechanical valves in the pulmonary position compared with other valves. Additionally, a more consistent follow-up of these patients in terms of echocardiographic, valve-related and warfarin-related complications is needed. With this information, clearer conclusions may be drawn when considering their role.

Hybrid approach to closure of an acquired coronary-cameral fistula.

Coronary-cameral fistula is an abnormal fistulous communication between a coronary artery and a cardiac chamber. Significant fistulae require closure either percutaneously or surgically to avoid any complications. We describe the case of a 19-year-old male patient with tetralogy of Fallot, who presented with a complex coronary-cameral fistula, which precluded percutaneous occlusion. By means of a hybrid approach, the fistula was easily located and closed surgically. Where surgical correction of such fistulae is warranted in the setting of other cardiac defects, a hybrid approach to isolate the fistula followed by surgical intervention will reduce operative time, thereby potentially lowering perioperative complications.

Mechanical Aortic Valve-on-Valve Replacement in Previous Bentall Procedure: An Alternate Technique

Acute aortic valve regurgitation due to thrombosed prosthetic valve can present as a surgical emergency. This article reports a successful and unusual management of a young pregnant female patient who presented with acute aortic valve regurgitation due to a thrombosed mechanical aortic valve. As the patient had previous multiple cardiac surgeries, the options were limited for repeat aortic valve or aortic root replacement. The patient had caesarean section followed by implantation of a mechanical valve-on-valve in a previously placed composite valved conduit. This technique may be useful for reoperative valve replacement in the setting of a prior mechanical Bentall patient.

Prosthetic Valve-on-Valve Mitral Valve Re-Replacement: A Novel Approach

Repeat mitral valve replacement in patients who underwent mechanical replacement during infancy may be technically very difficult due to the small-sized annulus accommodating the prosthesis. That can lead to dense fibrosis of the small annulus onto the sewing cuff. An attempt at explanting the prosthesis carries high risk of circumflex coronary artery injury or atrioventricular junction disruption. We present a novel approach to prevent a disaster in such a difficult scenario-implanting the new prosthesis above the previous prosthetic housing after removing the prosthetic leaflets.

Cardiopulmonary exercise testing in the evaluation of liver disease in adults who have had the Fontan operation

BACKGROUND Liver disease (LD) is a long-term complication in patients with a single ventricle who have had the Fontan operation. A decline in cardiopulmonary exercise testing (CPET) variables is associated with increased risk of hospitalization, but its association with LD is unknown. AIM To determine the association between CPET variables and LD in adults who have had the Fontan operation. METHODS We retrospectively reviewed the medical records from two tertiary institutions. RESULTS We identified 114 adults (≥18 years; mean 30.9±7.4 years) who had undergone the Fontan operation: 56% were women; 63% had total cavopulmonary connection; 66% had New York Heart Association (NYHA) class I status; 42% had arrhythmias; 22% had systemic right ventricle; and 35% had ventricular dysfunction. Of 81 patients with liver-imaging data, 41% had LD (i.e. imaging evidence of cirrhosis, with or without portal hypertension, splenomegaly or varices). There were no differences in clinical or echocardiographic variables between those with and without LD. Among the 58 patients with CPET data, mean peak oxygen consumption (VO2) was 18.6±5.7mL/kg/min, per-cent-predicted peak VO2 was 53.9±15.5%, peak oxygen pulse was 9.3±2.9mL/beat and per-cent-predicted peak oxygen pulse was 82.6±21.5%. Of the 44 patients with liver and CPET data, each standard deviation decrease in per-cent-predicted peak VO2 (16%) and per-cent-predicted peak oxygen pulse (22%) was associated with a 2.3-fold increase in the odds of LD, after adjusting for NYHA, institution and Fontan type (P=0.04). Similarly, each standard deviation decrease in per-cent-predicted peak VO2 and oxygen pulse was associated with an estimated 5.9-year and 4.9-year earlier onset of LD, respectively (P>0.05). CONCLUSIONS Decline in per-cent-predicted peak VO2 and oxygen pulse was associated with increased odds of LD in adults who had undergone the Fontan operation. Our study supports more rapid hepatic evaluation among patients with abnormal or worsening CPET variables.

Systolic Anterior Motion Obstructing the Pulmonary Outflow Tract After Tricuspid Valve Replacement

A patient with congenitally corrected transposition of the great arteries who presented with shortness of breath was found to have severe tricuspid regurgitation and right ventricular impairment. After uneventful mechanical systemic tricuspid atrioventricular valve replacement, the patient was extubated within 12 hours. On the first postoperative day, he developed episodes of profound hypotension lasting a few seconds. A transesophageal echocardiogram demonstrated displacement of the interventricular septum that caused systolic anterior motion of the mitral valve into the subpulmonic left ventricle. Mitral valve replacement resolved this complication, and the patient proceeded to do well at discharge.

Late bidirectional glenn anastomosis in a 54-year-old patient with unoperated functionally univentricular heart.

We report the case of a 54-year-old patient with complex univentricular physiology who presented with worsening exercise intolerance, chronic cyanosis, and uncontrolled heart failure. Investigations included echocardiography, cardiac magnetic resonance imaging, and cardiac catheterization. After discussion in a multidisciplinary meeting, the patient underwent successful surgery that included a bidirectional Glenn anastomosis and repair of the atrioventricular (AV) junction. She recovered well and on follow-up had substantially less cyanosis and heart failure. We demonstrated that common AV valve repair and Glenn shunt can be used together successfully in appropriately selected older patients as palliation for complex congenital heart disease with functionally univentricular physiology.

Congenital and acquired heart disease converge: ischaemic heart disease with a background of scimitar syndrome

A 66-year-old woman presented with NYHA and CCS class III symptoms. On questioning, her breathlessness was found to trace back to young adulthood worsening over time, and her angina was found to be present only in the preceding 5 months. Medical history included chronic obstructive pulmonary disease, cerebrovascular accident, peptic ulcer disease, and hypothyroidism. Chest roentgenogram demonstrated an …