Predictive Factors for Postoperative Intensive Care Unit Admission and Mechanical Ventilation After Cardiac Catheterization for Pediatric Pulmonary Vein Stenosis.

OBJECTIVE: To investigate the predictive factors for postoperative intensive care unit (ICU) admission and mechanical ventilation (MV) after cardiac catheterization for pediatric pulmonary vein stenosis (PVS). DESIGN: A retrospective observational study. SETTING: At a single tertiary academic pediatric medical center. PARTICIPANTS: Four hundred seventy-three pediatric patients diagnosed with PVS and who underwent cardiac catheterization from 2011 to 2021. MEASUREMENTS AND MAIN RESULTS: Univariate and multivariate analyses were performed for associated risk factors. The incidence of postoperative ICU admission was 46.5% (n = 220); among these, 93.4% (n = 206) required MV. Independent risk factors included male sex (odds ratio [OR] 3.93, p = 0.002 in ICU group; OR 2.89, p = 0.013 in MV group), low body weight (OR 0.80, p = 0.003 in ICU group; OR 0.79, p = 0.002 in MV group), preoperative oxygen supplement (OR 4.01, p = 0.002 in ICU group; OR 3.67, p = 0.003 in MV group), high PVS severity score (OR 1.15, p = 0.028 in ICU group), intraoperative hypotension requiring inotrope (OR 4.03, p = 0.011 in ICU group; OR 2.89, p = 0.035 in MV group), intraoperative red blood cell transfusion (OR 3.25, p = 0.023 in ICU group; OR 4.09, p = 0.005 in MV group), low preintervention PaO2/FIO2 ratio (OR 0.63, p = 0.009 in ICU group; OR 0.59, p = 0.002 in MV group), and high preintervention right ventricular systolic pressure (OR 1.39, p = 0.004 in ICU group; OR 1.27, p = 0.023 in MV group). CONCLUSION: The incidences of postoperative ICU admission and MV in this subgroup were relatively high. The identification of risk factors is useful in predicting and triaging the need for postoperative ICU admission and MV for the improvement of patient care.

Pulmonary Vein Stenosis After Second-Generation Cryoballoon Ablation.

BACKGROUND: Pulmonary vein stenosis (PVST) can occur after first-generation cryoballoon ablation. This study aimed to evaluate the incidence, severity, and characteristics of PVST after second-generation cryoballoon ablation. METHODS: In total, 103 patients underwent PV isolation of paroxysmal atrial fibrillation using second-generation cryoballoons with a single big-balloon 3-minute freeze technique. Cardiac enhanced multidetector computed tomography (MDCT) was performed both before and a median of 6.0 (4.0-8.0) months after the procedure in all. PVST was classified as follows: minimal (<25%), mild (25-50%), moderate (50-70%), or severe (>70%). RESULTS: In total, 406 PVs were analyzed. MDCT demonstrated PV stenosis in 10(2.5%) PVs among 8(7.8%) patients. In detail, minimal and mild PVSTs were observed in 6 and 4 PVs, respectively. PVST occurred in the left superior (LSPV), left inferior, and right superior PVs in 6, 1, and 3 PVs, respectively. No stenosis was observed in 15 PVs with active balloon deflations during freezing. All PVSTs had concentric patterns except for 2 PVs with minimal stenosis. Balloon deformities were observed during freezing of 2 PVs with mild stenosis. When the PVST was defined as a >25% decreased diameter, the incidence was 0.98% (4/406; including 3 LSPVs). PVST did not progress further during the follow-up period. CONCLUSIONS: Although the incidence of PVST was low, it could occur even if a single big-balloon short freeze technique was applied. The risk of PV stenosis significantly differed among the 4 PVs, and reaching balloon temperatures of -60 °C and active balloon deflations during freezing were not associated with any PV stenosis.

Primary Pulmonary Vein Stenosis: A New Look at a Rare but Challenging Disease.

Primary pulmonary vein stenosis (PPVS) represents a rare but emerging, often progressive heterogeneous disease with high morbidity and mortality in the pediatric population. Although our understanding of PPVS disease has improved markedly in recent years, much remains unknown regarding disease pathogenesis, distinct disease phenotypes, and patient- and disease-related risk factors driving the unrelenting disease progression characteristic of PPVS. In the pediatric population, risk factors identified in the development of PPVS include an underlying congenital heart disease, prematurity and associated conditions, and an underlying genetic or congenital syndrome. Continued improvement in the survival of high-risk populations, coupled with ongoing advances in general PPVS awareness and diagnostic imaging technologies suggest that PPVS will be an increasingly prevalent disease affecting pediatric populations in the years to come. However, significant challenges persist in both the diagnosis and management of PPVS. Standardized definitions and risk stratification for PPVS are lacking. Furthermore, evidence-based guidelines for screening, monitoring, and treatment remain to be established. Given these limitations, significant practice variation in management approaches has emerged across centers, and contemporary outcomes for patients affected by PPVS remain guarded. To improve care and outcomes for PPVS patients, the development and implementation of universal definitions for disease and severity, as well as evidence-based guidelines for screening, monitoring, cardiorespiratory care, and indications for surgical intervention will be critical. In addition, collaboration across institutions will be paramount in the creation of regionalized referral centers as well as a comprehensive patient registry for those requiring pulmonary vein stenosis.

Primary pulmonary vein stenosis among premature infants with single-vessel disease.

OBJECTIVES: Describe outcomes among preterm infants diagnosed with single-vessel primary pulmonary vein stenosis (PPVS) initially treated using conservative management (active surveillance with deferral of treatment). STUDY DESIGN: Retrospective cohort study at a single, tertiary-center (2009-2019) among infants <37 weeks' gestation with single-vessel PPVS. Infants were classified into two categories: disease progression and disease stabilization. Cardiopulmonary outcomes were examined, and a Kaplan-Meier survival analysis performed. RESULTS: Twenty infants were included. Compared to infants in the stable group (0/10, 0%), all infants in the progressive group had development of at least severe stenosis or atresia (10/10, 100%; P < 0.01). Severe pulmonary hypertension at diagnosis was increased in the progressive (5/10, 50%) versus the stable group (0/10, 0%; P = 0.03). Survival was lower among infants in the progressive than the stable group (log-rank test, P < 0.01). CONCLUSION: Among preterm infants with single-vessel PPVS, risk stratification may be possible, wherein more targeted, individualized therapies could be applied.

Pulmonary Vein Stenosis After Atrial Fibrillation Ablation: Insights From the ADVICE Trial.

BACKGROUND: Pulmonary vein (PV) stenosis is a complication of atrial fibrillation (AF) ablation. The incidence of PV stenosis after routine post-ablation imaging remains unclear and is limited to single-centre studies. Our objective was to determine the incidence and predictors of PV stenosis following circumferential radiofrequency ablation in the multicentre Adenosine Following Pulmonary Vein Isolation to Target Dormant Conduction Elimination (ADVICE) trial. METHODS: Patients with symptomatic AF underwent circumferential radiofrequency ablation in one of 13 trial centres. Computed tomographic (CTA) or magnetic resonance (MRA) angiography was performed before ablation and 90 days after ablation. Two blinded reviewers measured PV diameters and areas. PVs with stenosis were classified as severe (> 70%), moderate (50%-70%), or mild (< 50%). Predictors of PV stenosis were identified by means of multivariable logistic regression. RESULTS: A total of 197 patients (median age 59.5 years, 29.4% women) were included in this substudy. PV stenosis was identified in 41 patients (20.8%) and 47 (8.2%) of 573 ablated PVs. PV stenosis was classified as mild in 42 PVs (7.3%) and moderate in 5 PVs (0.9%). No PVs had severe stenosis. Both cross-sectional area and diameter yielded similar classifications for severity of PV stenosis. Diabetes was associated with a statistically significant increased risk of PV stenosis (OR 4.91, 95% CI 1.45-16.66). CONCLUSIONS: In the first systematic multicentre evaluation of post-ablation PV stenosis, no patient acquired severe PV stenosis. Although the results are encouraging for the safety of AF ablation, 20.8% of patients had mild or moderate PV stenosis, in which the long-term effects are unknown.

Anatomical and Procedural Factors of Severe Pulmonary Vein Stenosis After Cryoballoon Pulmonary Vein Ablation.

OBJECTIVES: This study examined the anatomical or procedural factors associated with severe pulmonary vein (PV) stenosis after cryoballoon PV isolation. BACKGROUND: PV stenosis is a complication associated with cryoballoon ablation. METHODS: The study included 170 consecutive patients with paroxysmal atrial fibrillation who underwent cryoballoon ablation. In addition to factors generally considered to be related to the occurrence of PV stenosis (PV size, cryoballoon application number and time, and minimum freezing temperature), we evaluated the following 4 factors: 1) depth of balloon position; 2) the PV angle (internal angle between each PV and horizontal line); 3) noncoaxial balloon placement (hemispherical occlusion); and 4) contact surface area between the cryoballoon and the PV wall (defined as the balloon contact ratio). RESULTS: Severe PV stenosis (≥75% area reduction) was observed in 9 (1.3%) PVs (6 left superior and 3 right superior PVs) in 9 patients. The PV size, cryoballoon application number and time, minimum freezing temperature, and the depth of cryoballoon position were not significantly associated with occurrence of severe PV stenosis, but the PV angle was significantly smaller in PVs with severe stenosis than it was in those without stenosis (25.6 ± 9.7° vs. 34.2 ± 6.4°; p < 0.001). Hemispherical occlusion was more frequently observed and balloon contact ratio was larger in PVs with severe stenosis (55.6% vs. 14.8%; p = 0.049) than in those without stenosis (0.70 ± 0.06 vs. 0.54 ± 0.08; p < 0.001). CONCLUSIONS: A horizontally connecting PV, noncoaxial placement of cryoballoon, and a larger contact surface area of the cryoballoon were predictors of the occurrence of severe PV stenosis after cryoballoon ablation.

Predictors for Residual Pulmonary Vascular Obstruction after Unprovoked Pulmonary Embolism: Implications for Clinical Practice-The PADIS-PE Trial.

BACKGROUND: We aimed to identify risk factors for residual pulmonary vascular obstruction after a first unprovoked pulmonary embolism (PE). METHODS: Analyses were based on data from the double-blind randomized "PADIS-PE" trial that included 371 patients with a first unprovoked PE initially treated during 6 uninterrupted months; all patients underwent baseline ventilation-perfusion lung scanning at inclusion (i.e., after 6 months of anticoagulation). Each patient's pulmonary vascular obstruction indexes (PVOIs) at PE diagnosis and at inclusion were centrally assessed. RESULTS: Among the 371 included patients, residual PVOI was available in 356 patients, and 150 (42.1%) patients had PVOI ≥ 5%. At multivariable analysis, age > 65 years (odds ratio [OR], 2.81, 95% confidence interval [CI], 1.58-5.00), PVOI ≥ 25% at PE diagnosis (OR, 3.53, 95% CI, 1.94-6.41), elevated factor VIII (OR, 3.89, 95% CI, 1.41-10.8), and chronic respiratory disease (OR, 2.18, 95% CI, 1.11-4.26) were independent predictors for residual PVOI ≥ 5%. Patients with ≥ 1 of these factors represented 94.5% (123 patients) of all patients with residual PVOI ≥ 5%. CONCLUSION: Six months after a first unprovoked PE, age > 65 years, PVOI ≥ 25% at PE diagnosis, elevated factor VIII, or chronic respiratory disease were found to be independent predictors for residual pulmonary vascular obstruction. CLINICAL TRIALS REGISTRATION: URL: http://www.controlled-trials.com. Unique identifier: NCT00740883.

Balloon angioplasty versus stenting for pulmonary vein stenosis after pulmonary vein isolation for atrial fibrillation: A meta-analysis.

BACKGROUND: The incidence of pulmonary vein stenosis (PVS) as complication after pulmonary vein isolation (PVI) for atrial fibrillation (AF) has decreased in the last decade. However, as PVI for AF is becoming more prevalent, the incidence remains considerable in absolute terms. The purpose of this meta-analysis is to investigate the optimal approach for management of PVS after PVI for AF. METHODS AND RESULTS: We searched electronic scientific databases for studies comparing plain balloon angioplasty (BA) versus stenting for PVS after PVI for AF. Aggregate data were pooled to perform a meta-analysis. The primary and secondary outcomes were restenosis requiring repeated intervention and procedure-related complications, respectively. A total of 4 studies, treating 315 PVS in 188 patients (BA, n=171 versus stent, n=144 PVS) were considered. After a median follow-up of 32months, the overall incidence of restenosis was 46%. A percutaneous therapy with BA was associated with a higher risk for restenosis requiring repeat intervention compared to stent (risk ratio - RR, 95% confidence interval [95% CI]=2.18 [1.64-2.89], p<0.001). Procedure-related complications were comparable between BA and stent (RR [95% CI]=0.96 [0.19-4.96], p=0.96). The time to diagnosis of PVS after PVI for AF did not modify the treatment effect for the primary outcome with BA versus stent (p for interaction=0.16). CONCLUSIONS: In patients presenting PVS after PVI for AF, a percutaneous therapy with BA is associated with higher risk for restenosis requiring repeat intervention as compared to stent. These percutaneous therapies display comparable safety.

Contributors Toward Pulmonary Vein Restenosis Following Successful Intervention.

OBJECTIVES: This study sought to identify clinical and procedural risk factors associated with pulmonary vein (PV) restenosis. BACKGROUND: Pulmonary vein stenosis (PVS) is a rare but morbid complication of PV isolation for atrial fibrillation (AF) ablation. Interventions such as PV balloon angioplasty (BA) or stenting achieve excellent acute success; however, subsequent restenosis is common. METHODS: A total of 113 patients underwent invasive treatment for severe PVS between 2000 and 2014 and were followed prospectively. Baseline patient and lesion characteristics were abstracted from chart review and analyzed. Univariate and multivariate analyses were performed using patient and procedural characteristics to determine which factors were associated with an increased risk for subsequent PV restenosis. RESULTS: Over a median follow-up of 4.6 years there was PVS recurrence in 75 veins; 52 veins (57%) were treated with index BA and 23 veins were treated with stenting. After multivariate analysis, the only patient factor that was significantly associated with restenosis was a history of more than 1 AF ablation (hazard ratio [HR]: 1.91; 95% confidence interval [CI]: 1.07 to 3.41; p = 0.03). Multivariate analysis on a per-vein level demonstrated a significantly lower risk of restenosis in veins treated with a stent (HR: 2.84; 95% CI: 1.75 to 4.61; p < 0.0001). In veins treated with BA alone, inflation of the balloon to higher atmospheres significantly reduced the risk of recurrence (HR: 0.87; 95% CI: 0.78 to 0.98; p = 0.02). CONCLUSIONS: Restenosis is common after a successful PV intervention and the risk of restenosis is highest in those with a history of multiple AF ablations and in those treated with BA. Proceduralists should take into account the number of AF ablations a patient has undergone and should strongly consider stent deployment when intervening on PVS to reduce risk of restenosis.

Sutureless Versus Conventional Pulmonary Vein Repair: A Magnetic Resonance Pilot Study.

BACKGROUND: Two different surgical techniques are used to repair anomalous pulmonary venous connection or pulmonary vein (PV) stenosis: the classic repair (CR) and the sutureless repair (SR). The purpose of this study was to compare the prevalence of PV stenosis between the two surgical approaches. METHODS: Patients were prospectively recruited irrespective of symptoms or previous imaging findings. Cardiac magnetic resonance imaging and echocardiography were performed in a blinded fashion on the same day. RESULTS: Twenty-five patients (13 male) after PV repair completed the study. Twelve patients had undergone CR and 13 SR (in 1 patient as a reoperation after CR). The median age at operation was 2 months (range: 1 day to 5 years) and was similar for both groups; the median age at the time of cardiac magnetic resonance was 9 years (range: 6 to 17 years) and 9 years (range: 6 to 14 years) for the CR and SR, respectively. Four patients had PV stenosis. All 4 patients had had total anomalous pulmonary venous connection, 1 patient had undergone repair with the CR and 2 with a primary SR; 1 patient had first undergone a CR, followed by a SR for stenosis. Echocardiography provided complete visualization of all PVs in only 11 patients (44%). Notable stenosis of at least one PV was missed by echocardiography in 2 patients. CONCLUSIONS: This pilot study indicates that not only CR but also SR may be burdened by a risk of postoperative PV stenosis. Magnetic resonance imaging should be used routinely for the postoperative monitoring for the development of PV obstruction.

Incidence of Pulmonary Vein Stenosis After Radiofrequency Catheter Ablation of Atrial Fibrillation.

OBJECTIVES: This study aimed to determine incidence of pulmonary vein stenosis (PVS) and evaluate PVS-related symptoms. BACKGROUND: The real-life incidence of PVS after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) is unknown. METHODS: All patients who underwent RFCA of AF from 2005 to 2016 with routine pre- and post-ablation screening by magnetic resonance imaging or computed tomography were included. Primary ablation strategy was PV antrum isolation alone in all patients. PVS, defined as a significant reduction in the superoinferior or anteroposterior PV diameter, was classified as mild (30% to 50%), moderate (50% to 70%), or severe (>70%). RESULTS: Sufficient quality imaging of the PV anatomy before ablation and during follow-up (mean 6 ± 4 months) was performed in 976 patients (76.4% men, 59.1% paroxysmal AF). Of these patients, 306 (31.4%) showed mild stenosis, 42 (4.3%) revealed moderate stenosis, and 7 (0.7%) had a severe stenosis in at least 1 PV. Incidence of PVS fluctuated over the past decade. All severe PVS cases were likely caused by ablations being performed inside the PVs. Only 1 (0.1%) patient reported PVS-related symptoms of severe dyspnea during follow-up. Computed tomography revealed a subtotal occlusion of the left inferior PV and a severe stenosis of the left superior PV, requiring stenting. CONCLUSIONS: Although mild PVS was frequently observed after RFCA in this large cohort, incidence of severe PVS was <1% and incidence of symptomatic PVS necessitating intervention was negligible. Based on these findings, it seems appropriate to only screen for PVS in patients with suggestive symptoms.

Pulmonary vein stenosis of ex-premature infants with pulmonary hypertension and bronchopulmonary dysplasia, epidemiology, and survival from a multicenter cohort.

BACKGROUND: Pulmonary vein stenosis is emerging as an important clinical problem in ex-premature infants. METHODS: We sought to describe the epidemiology of pulmonary vein stenosis affecting ex-premature infants by a multicenter retrospective cohort study of patients from seven children's hospitals diagnosed between 2000-2014. RESULTS: We identified 39 ex-premature patients (26 males, median gestational age 28 weeks range 22-36 weeks, birth weight 1.1 kg range 433-2645-g) with pulmonary vein stenosis. Median age at diagnosis was 6.5 months (1 month-6 years). Presentation with pulmonary hypertension occurred in 26/39 (67%) and 29/39 (74%) had bronchopulmonary dysplasia, 15 (39%) were born of twin pregnancies with unaffected twin siblings. A median of 5 (range 1-25) echocardiograms was performed prior to diagnosis. The diagnosis was made using echocardiography in 22/39 (56%), by multi-detector contrast computed tomography scan (CT) in 8/39 (21%), cardiac catheterization in 6/39 (15%) patients, magnetic resonance imaging in 3/39 (8%). Freedom from death or re-stenosis was 73% at 1-year, 55% at 2, 5, and 10 years. Factors associated with shorter survival or re-stenosis were stenosis of ≥3 pulmonary veins (P < 0.01), bilateral pulmonary vein stenosis (P < 0.01) small for gestational age (P = 0.05), aged <6 months at diagnosis (P < 0.01). CONCLUSION: Pulmonary vein stenosis of ex-premature infants is a complex problem with poor survival, delayed diagnosis, and unsatisfactory treatment. The lack of concordance in twins suggests epigenetic or environmental factors may play a role in the development of pulmonary vein stenosis. In ex-premature infants with pulmonary hypertension and bronchopulmonary dysplasia a focused echocardiographic assessment of the pulmonary veins is required with further imaging if the echocardiogram is inconclusive.

Incidence and Factors Associated With the Occurrence of Pulmonary Vein Narrowing After Cryoballoon Ablation.

BACKGROUND: In contrast with traditional radiofrequency ablation, little is known about the influence of cryoballoon ablation on the morphology of pulmonary veins (PVs). We evaluated the influence of cryoballoon ablation on the PV dimension (PVD) and investigated the factors associated with a reduction of the PVD. METHODS AND RESULTS: Seventy-four patients who underwent cryoballoon ablation for paroxysmal atrial fibrillation were included in the present study. All subjects underwent contrast-enhanced computed tomography both before and at 3 months after the procedure. The PVD (cross-sectional area) was measured using a 3-dimensional electroanatomical mapping system. Each PV was evaluated according to the PVD reduction rate (ΔPVD), which was calculated as follows: (1-post-PVD/pre-PVD)×100 (%). Ninety-two percent of the PVs (271/296) were successfully isolated only by cryoballoon ablation; the remaining 8% of the PVs required touch-up ablation and were excluded from the analysis. Mild (25%-50%), moderate (50%-75%), and severe (≥75%) ΔPVD values were observed in 87, 14, and 3 PVs, respectively, including 1 case with severe left superior PV stenosis (ΔPVD: 94%) in a patient who required PV angioplasty. In multivariable analysis, a larger PV ostium and lower minimum freezing temperature during cryoballoon ablation were independently associated with PV narrowing (odds ratio, 1.773; P=0.01; and odds ratio, 1.137; P<0.001, respectively). CONCLUSIONS: A reduction of the PVD was often observed after cryoballoon ablation for atrial fibrillation. A larger PV ostium and lower minimum freezing temperature during cryoballoon ablation were associated with an increased risk of PVD reduction.

Pulmonary vein stenosis complicating radiofrequency catheter ablation for atrial fibrillation: A literature review.

Radiofrequency catheter ablation has become a widely used intervention in the treatment of atrial fibrillation. Pulmonary vein stenosis (PVS) is one of the most serious complications associated with this procedure; the degree of stenosis ranges from mild (<50%) to complete venous occlusion. The natural history of PVS and the risk of progression of existing PVS are uncertain. Symptomatic and/or severe PVS is a serious medical problem and can be easily misdiagnosed since it is an uncommon and relatively new medical problem, often has low clinical suspicion among clinicians, and has a non-specific presentation that mimics other more common respiratory or cardiac diseases. The estimated incidence varies in literature reports from 0% to 42% of ablation procedures, depending on technical aspects of the procedure and operator skill. Most patients with significant PVS remain asymptomatic or have few symptoms. Symptomatic patients usually present with dyspnea, chest pain, or hemoptysis and are usually treated with balloon angioplasty and/or stent placement. Little is known about the long term effect of PV stenosis/occlusion on the pulmonary circulation and the development of pulmonary hypertension. Evolving technology may reduce the frequency of this complication, but long term studies are needed to understand the effect of therapeutic atrial injury and adverse outcomes. This review summarizes the current literature and outlines an approach to the evaluation and management of these patients.