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Journal of Cardiothoracic Surgery Apr 2024Cardiac herniation occurs when there is a residual pericardial defect post thoracic surgery and is recognised as a rare but fatal complication. It confers a high...
BACKGROUND
Cardiac herniation occurs when there is a residual pericardial defect post thoracic surgery and is recognised as a rare but fatal complication. It confers a high mortality and requires immediate surgical correction upon recognition. We present a case of cardiac herniation occurring post thymectomy and left upper lobectomy.
CASE PRESENTATION
Initial presentation: A 48-year-old male, hypertensive smoker presented with progressive breathlessness and was found to have a left upper zone mass confirmed on CT biopsy as carcinoid of unclear origin. PET-CT revealed avidity in a left anterior mediastinal area, left upper lobe (LUL) lung mass, mediastinal lymph nodes, and a right thymic satellite nodule. Intraoperatively: Access via left thoracotomy and sternotomy. The LUL tumour involved the left thymic lobe (LTL), left superior pulmonary vein (LSPV), left phrenic nerve and intervening mediastinal fat and pericardium, which were resected en-masse. The satellite nodule in the right thymic lobe (RTL) was adjacent to the junction between the left innominate vein and superior vena cava (SVC). The pericardium was resected from the SVC to the left atrial appendage. Clinical deterioration: Initially the patient was doing well clinically on day 1, however there was sudden bradycardia, hypotension, clamminess, and oligoanuria, with raised central venous pressures and troponins. ECG: no capture in leads V1-2, but positive deflections seen on posterior leads. Echo: no acoustic windows, but good windows seen posteriorly. CXR: left mediastinal shift. Redo operation: After initial resuscitation and stabilisation on the intensive care unit, on day 2 a redo-sternotomy revealed cardiac herniation into the left thoracic cavity with the left ventricular apex pointing towards the spine, and inferior caval kinking. After reduction and repair of the pericardial defect with a fenestrated GoreTex patch, the patient recovered well with complete resolution of the ECG and CXR.
CONCLUSION
Cardiac herniation can even occur following sub-pneumonectomy lung resections and should be considered as a differential when faced with a sudden clinical deterioration, warranting early surgical correction.
Topics: Male; Humans; Middle Aged; Thymectomy; Vena Cava, Superior; Positron Emission Tomography Computed Tomography; Clinical Deterioration; Heart Diseases; Hernia; Pneumonectomy
PubMed: 38627781
DOI: 10.1186/s13019-024-02713-y -
Europace : European Pacing,... May 2024Pulmonary vein isolation using cryoablation is effective and safe in patients with atrial fibrillation (AF). Although both obesity and underweight are associated with a...
Association between body mass index and results of cryoballoon ablation in Korean patients with atrial fibrillation: an analysis from the Korean Heart Rhythm Society Cryoablation registry.
AIMS
Pulmonary vein isolation using cryoablation is effective and safe in patients with atrial fibrillation (AF). Although both obesity and underweight are associated with a higher risk for incident AF, there is limited data on the efficacy and safety following cryoablation according to body mass index (BMI) especially in Asians.
METHODS AND RESULTS
Using the Korean Heart Rhythm Society Cryoablation registry, a multicentre registry of 12 tertiary hospitals, we analysed AF recurrence and procedure-related complications after cryoablation by BMI (kg/m2) groups (BMI < 18.5, underweight, UW; 18.5-23, normal, NW; 23-25, overweight, OW; 25-30, obese Ⅰ, OⅠ; ≥30, obese Ⅱ, OⅡ). A total of 2648 patients were included (median age 62.0 years; 76.7% men; 55.6% non-paroxysmal AF). Patients were categorized by BMI groups: 0.9% UW, 18.7% NW, 24.8% OW, 46.1% OI, and 9.4% OII. Underweight patients were the oldest and had least percentage of non-paroxysmal AF (33.3%). During a median follow-up of 1.7 years, atrial arrhythmia recurred in 874 (33.0%) patients (incidence rate, 18.9 per 100 person-years). After multivariable adjustment, the risk of AF recurrence was higher in UW group compared with NW group (adjusted hazard ratio, 95% confidence interval; 2.55, 1.18-5.50, P = 0.02). Procedure-related complications occurred in 123 (4.7%) patients, and the risk was higher for UW patients (odds ratio, 95% confidence interval; 2.90, 0.94-8.99, P = 0.07), mainly due to transient phrenic nerve palsy.
CONCLUSION
Underweight patients showed a higher risk of AF recurrence after cryoablation compared with NW patients. Also, careful attention is needed on the occurrence of phrenic nerve palsy in UW patients.
Topics: Humans; Atrial Fibrillation; Cryosurgery; Male; Female; Middle Aged; Registries; Body Mass Index; Republic of Korea; Aged; Treatment Outcome; Recurrence; Risk Factors; Pulmonary Veins; Obesity; Thinness; Time Factors; Postoperative Complications
PubMed: 38624037
DOI: 10.1093/europace/euae095 -
Cureus Apr 2024The article reviews the anatomical path of the phrenic nerve and its anastomoses, with the most up-to-date knowledge reported in the literature. We have briefly reviewed... (Review)
Review
The article reviews the anatomical path of the phrenic nerve and its anastomoses, with the most up-to-date knowledge reported in the literature. We have briefly reviewed the possible phrenic dysfunctions, with the final aim of presenting an osteopathic manual approach for the treatment of the most superficial portion of the nerve, using a gentle technique. The approach we propose is, therefore, a theory based on clinical experience and the rationale that we can extrapolate from the literature. We hope that the article will be a stimulus for further experimental investigations using the technique illustrated in the article. To the authors' knowledge, this is the first article that takes into consideration the hypothesis of an osteopathic treatment with gentle techniques for the phrenic nerve.
PubMed: 38606024
DOI: 10.7759/cureus.58012 -
Europace : European Pacing,... Mar 2024Phrenic nerve injury (PNI) is the most common complication during cryoballoon ablation. Currently, two cryoballoon systems are available, yet the difference is unclear.... (Observational Study)
Observational Study Comparative Study
AIMS
Phrenic nerve injury (PNI) is the most common complication during cryoballoon ablation. Currently, two cryoballoon systems are available, yet the difference is unclear. We sought to compare the acute procedural efficacy and safety of the two cryoballoons.
METHODS
This prospective observational study consisted of 2,555 consecutive atrial fibrillation (AF) patients undergoing pulmonary vein isolation (PVI) using either conventional (Arctic Front Advance) (AFA-CB) or novel cryoballoons (POLARx) (POLARx-CB) at 19 centers between January 2022 and October 2023.
RESULTS
Among 2,555 patients (68.8 ± 10.9 years, 1,740 men, paroxysmal AF[PAF] 1,670 patients), PVIs were performed by the AFA-CB and POLARx-CB in 1,358 and 1,197 patients, respectively. Touch-up ablation was required in 299(11.7%) patients. The touch-up rate was significantly lower for POLARx-CB than AFA-CB (9.5% vs. 13.6%, p = 0.002), especially for right inferior PVs (RIPVs). The touch-up rate was significantly lower for PAF than non-PAF (8.8% vs. 17.2%, P < 0.001) and was similar between the two cryoballoons in non-PAF patients. Right PNI occurred in 64(2.5%) patients and 22(0.9%) were symptomatic. It occurred during the right superior PV (RSPV) ablation in 39(1.5%) patients. The incidence was significantly higher for POLARx-CB than AFA-CB (3.8% vs. 1.3%, P < 0.001) as was the incidence of symptomatic PNI (1.7% vs. 0.1%, P < 0.001). The difference was significant during RSPV (2.5% vs. 0.7%, P < 0.001) but not RIPV ablation. The PNI recovered more quickly for the AFA-CB than POLARx-CB.
CONCLUSIONS
Our study demonstrated a significantly higher incidence of right PNI and lower touch-up rate for the POLARx-CB than AFA-CB in the real-world clinical practice.
Topics: Humans; Phrenic Nerve; Male; Female; Atrial Fibrillation; Pulmonary Veins; Aged; Cryosurgery; Prospective Studies; Incidence; Registries; Peripheral Nerve Injuries; Middle Aged; Treatment Outcome; Catheter Ablation
PubMed: 38588039
DOI: 10.1093/europace/euae092 -
Cureus Mar 2024Regional anaesthesia for shoulder surgery remains challenging in patients with pre-existing respiratory comorbidities. Various alternative phrenic sparing techniques...
Regional anaesthesia for shoulder surgery remains challenging in patients with pre-existing respiratory comorbidities. Various alternative phrenic sparing techniques have been described in the literature, but to our knowledge, none have explored the benefits of using short-acting local anaesthetics in combination to achieve surgical anaesthesia for awake surgery. This case report describes the successful use of the superior trunk block catheter, a relative phrenic sparing shoulder nerve block, and 2% chloroprocaine, a short-acting local anaesthetic, to provide surgical anaesthesia for awake shoulder surgery in a patient with severe respiratory disease.
PubMed: 38586677
DOI: 10.7759/cureus.55761 -
Journal of Cardiothoracic Surgery Apr 2024A frequent complication of Fontan operations is unilateral diaphragmatic paresis, which leads to hemodynamic deterioration of the Fontan circulation. A potential new...
BACKGROUND
A frequent complication of Fontan operations is unilateral diaphragmatic paresis, which leads to hemodynamic deterioration of the Fontan circulation. A potential new therapeutic option is the unilateral diaphragmatic pacemaker. In this study, we investigated the most effective stimulation location for a potential fully implantable system in a porcine model.
METHODS
Five pigs (20.8 ± 0.95 kg) underwent implantation of a customized cuff electrode placed around the right phrenic nerve. A bipolar myocardial pacing electrode was sutured adjacent to the motor point and peripherally at the costophrenic angle (peripheral diaphragmatic muscle). The electrodes were stimulated 30 times per minute with a pulse duration of 200 µs and a stimulation time of 300 ms. Current intensity was the only variable changed during the experiment.
RESULTS
Effective stimulation occurred at 0.26 ± 0.024 mA at the phrenic nerve and 7 ± 1.22 mA at the motor point, a significant difference in amperage (p = 0.005). Even with a maximum stimulation of 10 mA at the peripheral diaphragm muscle, however, no effective stimulation was observed.
CONCLUSION
The phrenic nerve seems to be the best location for direct stimulation by a unilateral thoracic diaphragm pacemaker in terms of the required amperage level in a porcine model.
Topics: Humans; Child; Swine; Animals; Phrenic Nerve; Diaphragm; Respiratory Paralysis; Electrodes; Prostheses and Implants; Electric Stimulation
PubMed: 38580985
DOI: 10.1186/s13019-024-02707-w -
World Journal of Cardiology Mar 2024Thoracic ultrasound has attracted much interest in detecting pleural effusion or pulmonary consolidation after cardiac surgery. In 2016, Trovato reported, in the , the...
Thoracic ultrasound has attracted much interest in detecting pleural effusion or pulmonary consolidation after cardiac surgery. In 2016, Trovato reported, in the , the interest of using, in addition to echocardiography, thoracic ultrasound. In this editorial, we highlight the value of assessing diaphragm function after cardiac surgery and interventional cardiology procedures. Various factors are able to impair diaphragm function after such interventions. Diaphragm motion may be decreased by chest pain secondary to sternotomy, pleural effusion or impaired muscle function. Hemidiaphragmatic paralysis may be secondary to phrenic nerve damage complicating cardiac surgery or atrial fibrillation ablation. Diagnosis may be delayed. Indeed, respiratory troubles induced by diaphragm dysfunction are frequently attributed to pre-existing heart disease or pulmonary complications secondary to surgery. In addition, elevated hemidiaphragm secondary to diaphragm dysfunction is sometimes not observed on chest X-ray performed in supine position in the intensive care unit. Analysis of diaphragm function by ultrasound during the recovery period appears essential. Both hemidiaphragms can be studied by two complementary ultrasound methods. The mobility of each hemidiaphragms is measured by M-mode ultrasonography. In addition, recording the percentage of inspiratory thickening provides important information about the quality of muscle function. These two approaches make it possible to detect hemidiaphragm paralysis or dysfunction. Such a diagnosis is important because persistent diaphragm dysfunction after cardiac surgery has been shown to be associated with adverse respiratory outcome. Early respiratory physiotherapy is able to improve respiratory function through strengthening of the inspiratory muscles diaphragm and accessory inspiratory muscles.
PubMed: 38576518
DOI: 10.4330/wjc.v16.i3.118 -
Frontiers in Cardiovascular Medicine 2024Right phrenic nerve palsy is the most frequent complication of cryoballoon procedures. The SMARTFREEZE™ console (Boston Scientific, St. Paul, MN, USA) has integrated a...
BACKGROUND AND AIMS
Right phrenic nerve palsy is the most frequent complication of cryoballoon procedures. The SMARTFREEZE™ console (Boston Scientific, St. Paul, MN, USA) has integrated a new tool for diaphragm monitoring-the Diaphragm Movement Sensor; however, it has not been evaluated in clinical practice. We aimed to assess the diagnostic performance of the Diaphragm Movement Sensor based on compound motor action potential data recorded simultaneously.
METHODS
Thirty consecutive patients (mean age 63.2 ± 10.2 years) were included. We simultaneously recorded the compound motor action potential and the Diaphragm Movement Sensor during cryoapplications in the right pulmonary veins. The right phrenic nerve was paced at 60 per minute, 12 V and 2.9 ms. Compound motor action potential monitoring with a 30% decrease cutoff for the diagnosis of phrenic nerve threatening was considered the gold standard. The Diaphragm Movement Sensor decrease threshold was also set at 30%.
RESULTS
Considering compound motor action potential monitoring, phrenic nerve threatening occurred 11 times (in seven patients) among 84 cryoapplications (13.1%) at the right pulmonary veins. The sensitivity and specificity of the Diaphragm Movement Sensor were, respectively, 33% (95% CI: 7%-70%) and 49% (95% CI: 38%-61%; < 0.001). The predictive positive and negative values for the Diaphragm Movement Sensor were, respectively, 7% (95% CI: 2%-20%) and 86% (95% CI: 72%-95%). The Diaphragm Movement Sensor gave an erroneous diagnosis in 44/84 cryoapplications (52.4%).
CONCLUSIONS
The diagnostic performance of the Diaphragm Movement Sensor is low, and the relevance of its use in clinical practice may be debated.
PubMed: 38572304
DOI: 10.3389/fcvm.2024.1361761 -
Scientific Reports Mar 2024Orexin signaling plays a facilitatory role in respiration. Abnormalities in orexin levels correlate with disordered breathing patterns and impaired central respiratory...
Orexin signaling plays a facilitatory role in respiration. Abnormalities in orexin levels correlate with disordered breathing patterns and impaired central respiratory chemoreception. Nucleus tractus solitarii (NTS) neurons expressing the transcription factor Phox2b contribute to the chemoreceptive regulation of respiration. However, the extent to which orexinergic signaling modulates respiratory activity in these Phox2b-expressing NTS neurons remains unclear. In the present study, the injection of orexin A into the NTS significantly increased the firing rate of the phrenic nerve. Further analysis using fluorescence in situ hybridization and immunohistochemistry revealed that orexin 1 receptors (OX1Rs) were primarily located in the ventrolateral subdivision of the NTS and expressed in 25% of Phox2b-expressing neurons. Additionally, electrophysiological recordings showed that exposure to orexin A increased the spontaneous firing rate of Phox2b-expressing neurons. Immunostaining experiments with cFos revealed that the OX1R-residing Phox2b-expressing neurons were activated by an 8% CO stimulus. Crucially, OX1R knockdown in these NTS neurons notably blunted the ventilatory response to 8% CO, alongside an increase in sigh-related apneas. In conclusion, orexinergic signaling in the NTS facilitates breathing through the activation of OX1Rs, which induces the depolarization of Phox2b-expressing neurons. OX1Rs are essential for the involvement of Phox2b-expressing NTS neurons in the hypercapnic ventilatory response.
Topics: Solitary Nucleus; Orexins; Carbon Dioxide; In Situ Hybridization, Fluorescence; Respiration
PubMed: 38553555
DOI: 10.1038/s41598-024-58075-x -
Journal of Anesthesia Jun 2024We aimed to quantify perioperative changes in diaphragmatic function and phrenic nerve conduction in patients undergoing routine thoracic surgery. (Observational Study)
Observational Study
PURPOSE
We aimed to quantify perioperative changes in diaphragmatic function and phrenic nerve conduction in patients undergoing routine thoracic surgery.
METHODS
A prospective observational study was performed in patients undergoing esophageal resection or pulmonary lobectomy. Examinations were carried out the day prior to surgery, 3 days and 10-14 days after surgery. Endpoints for diaphragmatic function included ultrasonographic measurements of diaphragmatic excursion and thickening fraction. Endpoints for phrenic nerve conduction included baseline-to-peak amplitude, peak-to-peak amplitude, and transmission delay. Measurements were assessed on both the surgical side and the non-surgical side of the thorax.
RESULTS
Forty patients were included in the study. Significant reductions in diaphragmatic excursion were seen on the surgical side of the thorax for all excursion measures (posterior part of the right hemidiaphragm, p < 0.001; hemidiaphragmatic top point, p < 0.001; change in intrathoracic area, p < 0.001). Significant changes were seen for all phrenic nerve measures (baseline-to-peak amplitude, p < 0.001; peak-to-peak amplitude, p < 0.001; transmission delay, p = 0.041) on the surgical side. However, significant changes were also seen on the non-surgical side for all phrenic nerve measures (baseline-to-peak amplitude, p < 0.001; peak-to-peak amplitude, p < 0.001; transmission delay, p = 0.022). A postoperative reduction in posterior diaphragmatic excursion of more than 50% was significantly associated with postoperative pulmonary complications (coefficient: 2.69 (95% CI [1.38, 4.01], p < 0.001).
CONCLUSION
Thoracic surgery caused a significant unilateral reduction in diaphragmatic excursion on the surgical side of the thorax, which was accompanied by significant changes in phrenic nerve conduction. However, phrenic nerve conduction was also significantly affected on the non-surgical side to a lesser extent, which was not mirrored in diaphragmatic excursion. Our findings suggest that phrenic nerve paresis plays a role in postoperative diaphragmatic dysfunction, which may be a contributing factor in the pathogenesis of postoperative pulmonary complications.
CLINICAL TRIALS REGISTRATION NUMBER
NCT04507594.
Topics: Humans; Phrenic Nerve; Diaphragm; Male; Female; Postoperative Complications; Prospective Studies; Middle Aged; Aged; Thoracic Surgical Procedures; Paresis; Lung Diseases; Ultrasonography
PubMed: 38546897
DOI: 10.1007/s00540-024-03325-5