Danyal Khan

Percutaneous Tricuspid Valve Replacement in Congenital and Acquired Heart Disease

OBJECTIVES This study sought to describe the first human series of percutaneous tricuspid valve replacements in patients with congenital or acquired tricuspid valve (TV) disease. BACKGROUND Percutaneous transcatheter heart valve replacement of the ventriculoarterial (aortic, pulmonary) valves is established. Although there are isolated reports of transcatheter atrioventricular heart valve replacement (hybrid and percutaneous), this procedure has been less frequently described; we are aware of no series describing this procedure for TV disease. METHODS We approached institutions with significant experience with the Melody percutaneous pulmonary valve (Medtronic, Inc., Minneapolis, Minnesota) to collect data where this valve had been implanted in the tricuspid position. Clinical and procedural data were gathered for 15 patients. Indications for intervention included severe hemodynamic compromise and perceived high surgical risk; all had prior TV surgery and significant stenosis and/or regurgitation of a bioprosthetic TV or a right atrium-to-right ventricle conduit. RESULTS Procedural success was achieved in all 15 patients. In patients with predominantly stenosis, mean tricuspid gradient was reduced from 12.9 to 3.9 mm Hg (p < 0.01). In all patients, tricuspid regurgitation was reduced to mild or none. New York Heart Association functional class improved in 12 patients. The only major procedural complication was of third-degree heart block requiring pacemaker insertion in 1 patient. One patient developed endocarditis 2 months after implant, and 1 patient with pre-procedural multiorgan failure did not improve and died 20 days after the procedure. The remaining patients have well-functioning Melody valves in the TV position a median of 4 months after implantation. CONCLUSIONS In selected cases, patients with prior TV surgery may be candidates for percutaneous TV replacement.

The use of three‐dimensional rotational angiography to assess the pulmonary circulation following cavo‐pulmonary connection in patients with single ventricle

Bi‐plane angiography is the gold standard for imaging the pulmonary arteries (PAs) after cavo‐pulmonary connection (CPC). Three‐dimensional rotational angiography (3DRA) is emerging technology that we hypothesized may enhance diagnostic capabilities in this patient group.

New approach to interstage care for palliated high-risk patients with congenital heart disease

OBJECTIVE Home surveillance monitoring might identify patients at risk for interstage death after stage 1 palliation for hypoplastic left heart syndrome. We sought to identify the effect that a high-risk program might have on interstage mortality and identification of residual/recurrent lesions after neonatal palliative operations. METHODS Between January 2006 to January 2010, newborns after stage 1 palliation for hypoplastic left heart syndrome or shunt placement were invited to participate in our high-risk program. Patients enrolled in our high-risk program comprise the study group. Patients who had similar operations between January 2002 and December 2005 comprise the control group. Comparisons are made between the 2 groups with respect to interstage mortality and the frequency and timing of interstage admissions requiring medical, catheter, or surgical treatment. RESULTS Seventy-two patients met the criteria for our high-risk program. Fifty-nine (82%) of 72 patients were enrolled. Among 19 patients with hypoplastic left heart syndrome in our high-risk program, outpatient interstage mortality was zero. Outpatient interstage mortality for the 36 control subjects with hypoplastic left heart syndrome was 6%. Among 40 patients with shunts in the study group, there was 1 outpatient interstage death compared with 4 (6%) deaths in 68 subjects in the control group. Significant residual/recurrent lesions were identified with similar frequency between the 2 groups. However, after shunt operations, these lesions were detected and treated at significantly younger mean ages for patients followed in the high-risk program (P < .005). CONCLUSIONS Initiation of a high-risk program might decrease interstage mortality after high-risk neonatal palliative operations. Such an approach might contribute to earlier detection of significant residual/recurrent lesions amenable to therapy.

CRISP: Catheterization RISk score for pediatrics: A Report from the Congenital Cardiac Interventional Study Consortium (CCISC)

We sought to develop a scoring system that predicts the risk of serious adverse events (SAEs) for individual pediatric patients undergoing cardiac catheterization procedures.

Mid-term Outcomes of the Helex Septal Occluder for Percutaneous Closure of Secundum Atrial Septal Defects

BACKGROUND The HELEX Septal Occluder (HSO) was approved by the Food and Drug Administration for closure of secundum atrial septal defects (ASD) in 2006. However, little mid-term follow-up information is available. The object of this study was to examine mid-term outcomes after HSO implantation METHODS A retrospective chart review was performed on the first 74 patients who underwent ASD closure with the HSO between 4/00-10/04. Only patients who left the catheterization laboratory after successful implantation and had a minimum follow-up of 5 years were selected for analysis. RESULTS Thirty-three patients met entry criteria. At implantation the mean age was 10.9 years and the median ASD size was 15.1 mm. At a median follow-up of 88 months, 26 patients had complete ASD closure, 6 had trivial left-right shunts, and 1 had a significant residual shunt having a reintervention. Fluoroscopy, performed in 27 patients revealed a frame fracture in 3 patients (9%), all of whom were asymptomatic and had effective ASD closure. All 3 devices were 30 mm or 35 mm HSO and were left in place. One patient developed first-degree heart block and remained asymptomatic with no progression. There were no instances of late device embolization, cardiac perforation, erosion, or death. CONCLUSIONS Following successful implantation, HSO results in effective closure of secundum ASD in mid-term follow-up. Late complications appear to be rare with the exception of frame fracture, which in this series did not result in clinical sequelae.

Hyperlactatemia in Neonates Admitted to the Cardiac Intensive Care Unit with Critical Heart Disease

Neonates with critical heart disease are at risk of significant deficiencies in systemic oxygen delivery. The incidence and clinical pattern of hyperlactatemia in neonates presenting with critical heart disease has not been described. We reviewed the lactate pattern of neonates transferred to our cardiac intensive care unit for surgical management of their heart disease over a 1-year period. Stabilization of these neonates began in the referring institutions. From 8/4/03 to 8/4/04, 75 neonates with critical heart disease were transferred to our unit for stabilization and subsequent surgery. Blood lactate was measured on admission and subsequently in any patient thought to be at risk of low systemic oxygen delivery. Lactate was measured in 59 patients on admission and in 63 patients within the first 48 h of admission. Median age on admission was 1 day (range 0–13). Median age at surgery was 8 days (range 1–30). Median length of stay was 20 days. Peak lactate was noted on admission in 51 patients, and at 12–24 h in 8 patients. Mild hyperlactatemia (2.3–5 mmol/l) was present in 30 patients on admission and moderate-to-severe hyperlactatemia (≧5 mmol/l) was present in 8 patients. Mean lactate level on admission was 3.1 ± 0.6 mmol/l, and this did not return to normal (<2.3 mmol/l) until 36 h after admission. Severe hyperlactatemia patients also were noted to have normal lactate levels by 36 h. The presence of hyperlactatemia did not affect length of stay or mortality. There were no preoperative deaths and 4 postoperative deaths (1 death in 38 patients with mild or severe hyperlactatemia). Hyperlactatemia is frequently present in neonates admitted to a tertiary care center for management of congenital heart disease. Blood lactate levels normalize within 36 h. The presence of preoperative hyperlactatemia, even when moderate-to-severe, does not have significant adverse effect on postoperative mortality.

Electrocardiogram before starting stimulant medications: to order or not?

D is an 8-year-old boy brought to his paediatrician for evaluation. His mother is concerned as his teacher has been frequently complaining that he is very restless and often disturbs the rest of the class by getting up on some pretext or the other. He is unable to concentrate on his work and gets distracted very easily. He makes many careless mistakes and can hardly finish his tasks on time. He is frequently reprimanded for talking during class. He often answers out of turn or before the question has been completed; however, so far, he has been managing to get passing grades. At home, he is constantly on the go while he is awake. If he is forced to sit, like at mealtimes, he fidgets a lot. He also needs to be constantly nagged to do everything, even his daily activities such as brushing his teeth, or he forgets to do them or leaves them incomplete. He takes ages to finish his food. It is a major job to get him to do his homework. His mother says that at home he has been like that since the last 2 to 3 years, but now she is concerned because of the difficulties he is experiencing at school as well. After obtaining his medical history, examination, and getting response from parents and teachers--using Vanderbuilt Assessment Scales--the paediatrician diagnoses him to have attention deficit hyperactivity disorder. Besides behavioural interventions, he considers medications for his management. The paediatrician is debating the merits of performing electrocardiogram and/or referring the boy to a cardiologist before starting stimulant medications. If you were caring for this patient, how would you proceed?

Physiologic limitation of omega exists in patients after the Norwood palliation and is underestimated by the arterial venous oxygen saturation difference.

BACKGROUND Survival after the Norwood palliation (NW) is dependent on maximizing systemic oxygen delivery. Omega (Omega) is used to express the excess of oxygen delivery to oxygen consumption. We hypothesized that an intrinsic deficiency in the ability to maximize the relationship between oxygen delivery (DO(2)) and oxygen consumption (VO(2)) is present in infants after NW and is underestimated by arterial venous oxygen saturation difference (a-vO(2)). METHODS Simultaneous arterial and systemic venous blood gas data were prospectively collected for the first 24 hours after surgery in 10 neonates after NW and 32 infants after biventricular repair (BV). Blood gas data were compared between groups. These data were compared with a group of 11 infants with hypoplastic left heart syndrome (HLHS) status post NW who were undergoing routine hemodynamic evaluation in the cardiac catheterization lab prior to a bidirectional Glenn operation (pre-Glenn). RESULTS The mean systemic arterial oxygen saturation was 77% for NW, 83% for pre-Glenn, and 97% for biventricular repair. NW group had a mean systemic venous oxygenation saturation (SvO(2)) of 47% (range 12-67%) vs. 67% (range 29-84%) in the BV group (P = .001). Pre-Glenn patients had a SvO(2) of 46 (not significant [NS] vs. NW, P = .001 vs. BV). In NW, a-vO(2) mean was 32 (range 15-63) compared with mean 32 (range 16-71) in BV group (NS). Pre-Glenn a-vO(2) mean was 33.6 (NS vs. NW or BV). Omega for NW group was 2.6 (range 1.1-4.2) and 3.4 (1.4-6.25) in BV group (P = .001). Omega for pre-Glenn was 2.5 (range 1.7-3.8) (NS vs. NW, P = .001 vs. BV). CONCLUSION Omega is lower for patients in the immediate postoperative period after NW and prior to their bidirectional Glenn operation than in patients after biventricular repair. This places NW patients closer to the critical point of DO(2) and therefore at greater risk for hemodynamic compromise than BV patients. The a-vO(2) difference underestimates this risk.