Repair of Aortic Regurgitation in Young Adults: Sooner Rather Than Later.

Background Establishing surgical criteria for aortic valve replacement (AVR) in severe aortic regurgitation in young adults is challenging due to the lack of evidence-based recommendations. We studied indications for AVR in young adults with severe aortic regurgitation and their outcomes, as well as the relationship between presurgical echocardiographic parameters and postoperative left ventricular (LV) size, function, clinical events, and valve-related complications. Methods and Results Data were collected retrospectively on 172 consecutive adult patients who underwent AVR or repair for severe aortic regurgitation between 2005 and 2019 in a tertiary cardiac center (age at surgery 29 [22-41] years, 81% male). One-third underwent surgery before meeting guideline indications. Postsurgery, 65% achieved LV size and function normalization. LV ejection fraction showed no significant change from baseline. A higher presurgical LV end-systolic diameter correlated with a lack of LV normalization (odds ratio per 1-cm increase 2.81, P<0.01). The baseline LV end-systolic diameter cut-off for predicting lack of LV normalization was 43 mm. Pre- and postoperative LV dimensions and postoperative LV ejection fraction predicted clinical events during follow-up. Prosthetic valve-related complications occurred in 20.3% during an average 5.6-year follow-up. Freedom from aortic reintervention was 98%, 96.5%, and 85.4% at 1, 5, and 10 years, respectively. Conclusions Young adult patients with increased baseline LV end-systolic diameter or prior cardiac surgery are less likely to achieve LV normalization after AVR. Clinicians should carefully balance the long-term benefits of AVR against procedural risks and future interventions, especially in younger patients. Evidence-based criteria for AVR in severe aortic regurgitation in young adults are crucial to improve outcomes.

Extracorporeal membrane oxygenation after prosthetic valve replacement in a child with neonatal Marfan syndrome: a case report.

Background: Neonatal Marfan syndrome (nMFS), the most severe form of Marfan syndrome, is a rare condition that presents a clinical and treatment challenge. nMFS has high infant mortality related to progressive valvular dysfunction. Valve replacement in this setting improves long-term prognosis but carries high morbidity and mortality. Thus, sharing clinical experience in treating such patients is valuable. Case summary: A 2 year old with nMFS underwent tricuspid valve annuloplasty and prosthetic mitral valve replacement. Postoperative management was complicated by pulmonary hypertension, cardiogenic shock, and arrythmias. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) helped overcome these challenges but posed a high risk for prosthetic valve thrombosis (PVT). Despite decompression of the left atrium (LA) with an LA vent, the left ventricle (LV) was distended because of aortic regurgitation and no native cardiac output. We lowered the ECMO flow under echocardiographic guidance; used inodilators and pacing to encourage transmitral flow and reduce LV afterload. The patient completed a successful 6-day ECMO run with good end-organ perfusion. At last follow up, she was 6 years old, enjoying school, home-ventilated through the tracheostomy, and mobilizing with walking aids/wheelchair. Discussion: Valve replacement can improve life quality and expectancy for patients with nMFS. Lowering ECMO flow under echocardiography guidance till the aortic valve is seen to open; coupled with inodilators, pacing and adequate anticoagulation can be a safe way to deliver VA-ECMO for cardiogenic shock after prosthetic valve replacement. Further research is needed to show if this strategy prevents prosthetic valve thrombosis and provides sufficient haemodynamic support and myocardial rest.

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.

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.

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.

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.

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.

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.

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.

Interleukin-10 and its role in clinical immunoparalysis following pediatric cardiac surgery.

OBJECTIVE: A systemic insult is associated with subsequent hyporesponsiveness to endotoxin (as measured by ex vivo tumor necrosis factor [TNF]-alpha production) and an increased risk of late nosocomial infection in some patients. When combined with low monocyte surface major histocompatibility complex class II expression, this state of altered host defense is now commonly referred to as immunoparalysis. This study was undertaken to delineate the relationship between observed levels of the anti-inflammatory cytokine interleukin-10, common genetic polymorphisms that influence these levels, and the occurrence and severity of endotoxin hyporesponsiveness in children following elective cardiac surgery requiring cardiopulmonary bypass. DESIGN: A prospective observational clinical study. SETTING: A tertiary pediatric cardiac center. PATIENTS: Thirty-six infants and children <2 yrs of age undergoing elective cardiac surgery requiring cardiopulmonary bypass. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We investigated the production of TNF-alpha, interleukin-6, interleukin-8, interleukin-1 receptor antagonist, and interleukin-10 in whole blood in response to lipopolysaccharide (Neisseria meningitides 10 ng/mL) in samples drawn before, during, and up to 48 hrs after surgery. Patients were genotyped for the -1082, -819, and -592 interleukin-10 promoter polymorphisms. Whole blood cytokine response to lipopolysaccharide was reduced postoperatively to 100 pg/mL) over the first 48 hrs were more likely to have an uncomplicated short stay (odds ratio 4.7, 95% confidence interval 1-22). CONCLUSIONS: Immediately following cardiac surgery, many children become relatively refractory to lipopolysaccharide stimulation. This immunoparalysis appears to be related in part to high circulating levels of interleukin-10 and places these patients at increased risk of postoperative complications. Interleukin-10 genotype may be a risk factor for immunoparalysis.

Does use of the Hepcon point-of-care coagulation monitor to optimise heparin and protamine dosage for cardiopulmonary bypass decrease bleeding and blood and blood product requirements in adult patients undergoing cardiac surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether use of the Hepcon point-of-care coagulation monitor (Medtronic, Minneapolis, MN) to optimise and monitor heparin and protamine dosage for cardiopulmonary bypass could decrease bleeding and blood and blood product requirements in adult patients undergoing cardiac surgery. Altogether 680 papers were identified on Medline, and 879 on Embase using the reported search strategy. Two further relevant papers were found by hand-searching of reference lists. Fourteen papers represented the best evidence on the topic. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses were tabulated. We conclude that in patients undergoing cardiac surgery, use of the Hepcon coagulation monitor will increase the dose of heparin but decrease the dose of protamine administered compared to more empirical ACT-based dosing regimes. There is some evidence that this leads to less activation of the coagulation system and may be associated with decreased postoperative bleeding and blood product requirements but more work is required to quantify the magnitude of this effect.

Acute coronary syndrome following repair of aortic dissection.

Cardiac complications associated with type A aortic dissections are relatively common before and during the surgical repair. A cardiac event occurring a few days after routine recovery is rare though. We describe a case of acute occlusion of the left anterior descending artery by thrombus, 4 days after surgical repair, salvaged by emergency angioplasty and stenting. A possible explanation for the thrombus includes embolisation of a fragment of glue.