All that Doesn't Enhance Isn't a Thrombus: Pitfalls Using Cardiac MRI TI 600 Sequence to Distinguish Between Cardiac Thrombus Versus Myxoma.

A 51-year-old male with a complicated medical history presented with shortness of breath. Preoperative workup confirmed the presence of a large atrial mass. However, delayed gadolinium enhancement CMR with long inversion time (TI 600) showed lack of enhancement, which was suggestive of a thrombus. During cardiac magnetic resonance imaging, delayed gadolinium enhancement sequences with long inversion time (TI 600) are commonly used to distinguish between an avascular thrombus versus a vascular tumor.

Uncommon using of the pulmonary homograft in oncological case - three years follow up.

INTRODUCTION: There are enough cases of colorectal cancer with liver metastasis, but inferior vena cava infiltraion with dissemination to the right atrium is an infrequent event. PRESENTATION OF CASE: This is the first case of surgical treatment of recurrent liver metastasis with the infiltration to the inferior vena cava and to the right atrium of the heart, using a cryopreserved pulmonary homograft. DISCUSSION: The choice of a cryopreserved pulmonary homograft was preferred by the need for a radical and wide resection of tissues involved in the metastasis, as well as to potentially reduce the risk of thrombosis in the short- and long-term postoperative period. CONCLUSION: The use of a cryopreserved homograft in operation undergoing cardiopulmonary bypass allowed us to perform the required volume of radical resection and to replace an extended section of the inferior vena cava.

Combination of electrophysiological mapping, radiofrequency catheter ablation, and atrial appendectomy in a 5-year-old girl with tachycardia-induced cardiomyopathy: a case report.

BACKGROUND: Atrial tachycardia (AT) originating from the left atrial appendage (LAA) is uncommon and the most difficult arrhythmia to eliminate. Therefore, we present the case of a 5-year-old girl with tachycardia-induced cardiomyopathy (TIC) caused by AT originating from the LAA and successfully treated with RFCA associated to left atrial appendectomy. With resolution of AT, we observed a progressive improvement of LV function. The effectiveness and safety of this combination therapy were evaluated over a one-month follow-up period. CASE PRESENTATION: A 5 -year-old female was evaluated for three days of incessant cough and a syncopal episode. Surface echocardiography and 24-hour monitoring showed that the infant had persistent atrial tachycardia. Echocardiography revealed an enlarged tele diastolic diameter (46.1 mm) and malfunctioning (EF 28.53%) left ventricle. The location of the lesion at the apex of the LAA was further confirmed by electrophysiological study and RFCA. After RFCA, the infant's ECG monitor showed that sinus rhythm was maintained for up to 22 h. Subsequently, atrial tachycardia recurred and sinus rhythm disappeared. Finally, atrial appendectomy was performed and sinus rhythm returned to normal. CONCLUSIONS: The heart function of the infant improved and sinus rhythm was maintained, further demonstrating the safety and effectiveness of combined treatment with RFCA and atrial appendectomy after electrophysiological localization of AT from LAA to TIC.

Surgical strategy for intravenous leiomyomatosis spreading from uterine to the right atrium presenting with recurrent syncope.

Uterine leiomyoma invading internal iliac vein and consequently disseminating into the right atrium is an extremely rare condition, and surgical strategy is controversial. Here, we reported a specific case with successful surgical resection through one-stage total hysterectomy, bilateral oophorectomy, and the intracardiovascular lesion. This procedure would be an optimal choice for uterine leiomyoma invading inferior vena cava and spreading to right atrium.

A rare presentation of primary cardiac myxofibrosarcoma: Case report and literature review.

BACKGROUND: Primary cardiac myxofibrosarcoma is a rare and aggressive malignancy, with the majority of approaching strategies relying on case reports. This article provides insights into its diagnosis and treatment. CASE PRESENTATION: This paper presents the case of a 40-year-old man with sudden onset hemoptysis, leading to the diagnosis of primary cardiac myxofibrosarcoma. Treatment involved open-heart surgery to excise the left atrium tumor, followed by 6 cycles of adjuvant chemotherapy. Unfortunately, brain metastasis developed, leading to the patient's death 1 year after initial diagnosis. CONCLUSION: Primary cardiac myxofibrosarcoma remains a clinical challenge with an unfavorable prognosis. Early diagnosis through advanced imaging is crucial, and research is needed to explore innovative treatments. This case underscores the complexities of managing this rare cardiac malignancy and highlights the necessity for ongoing investigations to enhance patient outcomes.

Impact of atrial fibrillation phenotype and left atrial volume on outcome after pulmonary vein isolation.

AIMS: Pulmonary vein isolation (PVI) is increasingly performed in patients with atrial fibrillation (AF). Both AF phenotype and left atrial (LA) volume have been shown to influence ablation outcome. The inter-relationship of the two is incompletely understood. We aimed to investigate the impact of AF phenotype vs. LA volume on outcome after PVI. METHODS AND RESULTS: In a retrospective analysis of a prospective registry of patients undergoing a first PVI, the association of AF phenotype and LA volume index (LAVI) was assessed as well as their impact on AF recurrence during follow-up. Overall, 476 patients were enrolled (median age 63 years, 29% females, 65.8% paroxysmal AF). Obesity, hypertension, chronic kidney disease, and heart failure were all significantly more frequent in persistent AF. After 1 year, single-procedure, freedom from arrhythmia recurrence was 61.5%. Patients with paroxysmal AF had better outcomes compared with patients with persistent AF (65.6 vs. 52.7%, P = 0.003), as had patients with no/mild vs. moderate/severe LA dilation (LAVI <42 mL/m2 67.1% vs. LAVI ≥42 mL/m2 53%, P < 0.001). The combination of both parameters refined prediction of 1-year recurrence (P < 0.001). After adjustment for additional clinical risk factors in multivariable Cox proportional hazard analysis, both AF phenotype and LAVI ≥42 mL/m2 contributed significantly towards the prediction of 1-year recurrence. CONCLUSION: Atrial fibrillation phenotype and LA volume are independent predictors of outcome after PVI. Persistent AF with no/mild LA dilation has a similar risk of recurrence as paroxysmal AF with a moderate/severe LA dilation and should be given similar priority for ablation.

Bleeding sites and treatment strategies for cardiac tamponade by catheter ablation requiring thoracotomy: risks of catheter ablation in patients with left atrial diverticulum.

BACKGROUND: There is insufficient information regarding the bleeding sites and surgical strategies of cardiac tamponade during catheter ablation for atrial fibrillation (AF). CASE PRESENTATION: Of the five patients with cardiac tamponade, three required surgical intervention and two required pericardiocentesis. In the first case of three cardiac tamponades requiring surgical intervention, considering that the peripheral route was used, the catecholamines did not reach the heart, and due to unstable vital signs, venoarterial extracorporeal membrane oxygenation (VA-ECMO) was inserted. No bleeding point was identified, but a thrombus had spread around the left atrium (LA) with diverticulum. Hemostasis was achieved with adhesives placed around the LA under on-pump beating. In the second case, pericardiocentesis was performed, but the patient showed heavy bleeding and unstable vital signs. Thus, VA-ECMO was inserted. Heavy bleeding was expected, and safety was enhanced by attaching a reservoir to the VA-ECMO. The bleeding point was found between the left upper pulmonary artery and LA under cardiac arrest to obtain a good surgical view for suturing repair. In the third case, the LA diverticulum was damaged. Pericardiocentesis resulted in stable vitals, but sustained bleeding was present. A bleeding point was found at the LA diverticulum, and suture repair under on-pump beating was performed. CONCLUSIONS: When cardiac tamponade occured in any patient with LA diverticulum, treatment could not be completed with pericardiocentesis alone, and thoracotomy was likely to be necessary. If the bleeding point could be confirmed, suturing technique is a more reliable surgical strategy than adhesive alone that leads to pseudoaneurysm. If the bleeding point is unclear, it is important to confirm the occurrence of LA diverticulum using a preoperative CT, and if confirmed, cover it with adhesive due to a high possibility of diverticulum bleeding. The necessity of CPB should be determined based on whether these operations can be completed while maintaining vital stability.

Electrophysiological cardiovascular MR: procedure-ready mesh model generation for interventional guidance based on non-selective excitation compressed sensing whole heart imaging.

Fully CMR-guided electrophysiological interventions (EP-CMR) have recently been introduced but data on the optimal CMR imaging protocol are scarce. This study determined the clinical utility of 3D non-selective whole heart steady-state free precession imaging using compressed SENSE (nsWHcs) for automatic segmentation of cardiac cavities as the basis for targeted catheter navigation during EP-CMR cavo-tricuspid isthmus ablation. Fourty-two consecutive patients with isthmus-dependent right atrial flutter underwent EP-CMR radiofrequency ablations. nsWHcs succeeded in all patients (nominal scan duration, 98 ± 10 s); automatic segmentation/generation of surface meshes of right-sided cavities exhibited short computation times (16 ± 3 s) with correct delineation of right atrium, right ventricle, tricuspid annulus and coronary sinus ostium in 100%, 100%, 100% and 95%, respectively. Point-by-point ablation adhered to the predefined isthmus line in 62% of patients (26/42); activation mapping confirmed complete bidirectional isthmus block (conduction time difference, 136 ± 28 ms). nsWHcs ensured automatic and reliable 3D segmentation of targeted endoluminal cavities, multiplanar reformatting and image fusion (e.g. activation time measurements) and represented the basis for precise real-time active catheter navigation during EP-CMR ablations of isthmus-dependent right atrial flutter. Hence, nsWHcs can be considered a key component in order to advance EP-CMR towards the ultimate goal of targeted substrate-based ablation procedures.

Management of left atrial myxoma in pregnant women: a case series.

BACKGROUND: Left atrial myxoma during pregnancy is rare. We present three cases in order to aid in the management. CASE PRESENTATION: Three cases of left atrial myxoma during pregnancy were presented in this article. Three patients all received multidisciplinary team work and acquired good outcomes. The case 1 had no symptoms and delivered before traditional cardiac surgery. The case 2 and case 3 undergone totally endoscopic minimally invasive cardiac surgery during pregnancy. The case 3 maintained pregnancy to term and gave birth to a healthy baby via vaginal delivery. No relapse of the tumor was observed. CONCLUSIONS: The management of left atrial myxoma during pregnancy ought to be individualized and combined with the gestational age. If the diagnosis was made in the first two trimesters of pregnancy, totally endoscopic minimally invasive cardiac surgery during pregnancy would be an optimal choice. The patients can benefit from the multidisciplinary team work.

Unusual presentation and delayed diagnosis of cardiac angiosarcoma.

BACKGROUND: Primary cardiac angiosarcomas are very rare and present aggressively with high rates of metastasis. Given the poor prognosis, particularly once disease has spread, early diagnosis and multidisciplinary treatment is essential. CASE PRESENTATION: We present the case of a 46-year-old male who presented with chest pain, intermittent fevers, and dyspnea. Workup with computed tomography scan and transesophageal echocardiography demonstrated a right atrial pseudoaneurysm. Given the concern for rupture, the patient was taken to the operating room, where resection of the pseudoaneurysm and repair using a bovine pericardial patch was performed. Histopathology report initially demonstrated perivascular lymphocyte infiltrate. Six weeks later, the patient represented with chest pain and new word finding difficulty. Workup revealed multiple solid lung, pericardial, brain, and bone nodules. Eventual biopsy of a cardiophrenic nodule demonstrated angiosarcoma, and rereview of the original pathology slides confirmed the diagnosis of primary cardiac angiosarcoma. CONCLUSIONS: Primary cardiac angiosarcomas are often misdiagnosed given the rarity of these tumors, but early diagnosis and initiation of treatment is essential. The unique presentation of our case demonstrates that clinical suspicion for cardiac angiosarcoma should be maintained for spontaneous pseudoaneurysm originating from the right atrium.

Proactive esophageal cooling during laser cardiac ablation: A computer modeling study.

BACKGROUND AND OBJECTIVES: Laser ablation is increasingly used to treat atrial fibrillation (AF). However, atrioesophageal injury remains a potentially serious complication. While proactive esophageal cooling (PEC) reduces esophageal injury during radiofrequency ablation, the effects of PEC during laser ablation have not previously been determined. We aimed to evaluate the protective effects of PEC during laser ablation of AF by means of a theoretical study based on computer modeling. METHODS: Three-dimensional mathematical models were built for 20 different cases including a fragment of atrial wall (myocardium), epicardial fat (adipose tissue), connective tissue, and esophageal wall. The esophagus was considered with and without PEC. Laser-tissue interaction was modeled using Beer-Lambert's law, Pennes' Bioheat equation was used to compute the resultant heating, and the Arrhenius equation was used to estimate the fraction of tissue damage (FOD), assuming a threshold of 63% to assess induced necrosis. We modeled laser irradiation power of 8.5 W over 20 s. Thermal simulations extended up to 250 s to account for thermal latency. RESULTS: PEC significantly altered the temperature distribution around the cooling device, resulting in lower temperatures (around 22°C less in the esophagus and 9°C in the atrial wall) compared to the case without PEC. This thermal reduction translated into the absence of transmural lesions in the esophagus. The esophagus was thermally damaged only in the cases without PEC and with a distance equal to or shorter than 3.5 mm between the esophagus and endocardium (inner boundary of the atrial wall). Furthermore, PEC demonstrated minimal impact on the lesion created across the atrial wall, either in terms of maximum temperature or FOD. CONCLUSIONS: PEC reduces the potential for esophageal injury without degrading the intended cardiac lesions for a variety of different tissue thicknesses. Thermal latency may influence lesion formation during laser ablation and may play a part in any collateral damage.

Potential arrhythmic substrate of atrial fibrillation at the left atrial diverticulum.

Catheter ablation therapy for persistent atrial fibrillation (PeAF) is both difficult and has limited outcomes. The mechanisms underlying the development and persistence of atrial fibrillation (AF) are not fully understood; therefore, ablation strategies are diverse. A 45-year-old man was referred to our hospital for persistent atrial fibrillation to undergo radiofrequency catheter insertion (RFCA). In the first session we conducted pulmonary vein isolation and additional linear ablation, including that of the roof line and posterior inferior line (posterior box lesion) as the stepwise ablation. However, AF was recurred in six months, therefore he was readmitted for second session ablation preoperative 3D computed tomography (CT) scan for drug-refractory PeAF was performed. The additional isolation of the left superior pulmonary vein and potential drivers of AF by mapping wavefront propagation using multipolar catheters by CARTOFINDER (Biosense Webster, Inc, Diamond Bar, CA, USA) was conducted. However, AF did not terminate. Tomography revealed that the left atrial (LA) diverticulum (LAD) was found uniquely. Electrophysiological findings showed focal firing of the myocardial sleeve and LA diverticulum by an approach for defragmented potentials by re-visiting in interval confidence level (ICL) mode included in the electroanatomical mapping system (CARTO 3, Biosense Webster, Inc, Diamond Bar, CA, USA) and the ablation by encircling this site finally made AF terminate. The AF has not recurred for more than 12 months without the use of antiarrhythmic drugs. This case report suggests that additional ablation around substrates in LAD may be effective for treating refractory AF.

Dizzy spells in pregnancy: successful antenatal removal of a huge left atrial myxoma with mitral valve obstruction.

Diagnosing atrial myxoma in pregnancy is challenging because patients may present with non-specific symptoms that might be overlooked. The timing of non-obstetric operation usually depends on the nature of the disease, after careful consideration of feto-maternal safety, including the use of cardiopulmonary bypass and placental transfer of anaesthetic drug. A woman in her 30s at 18 weeks of pregnancy presented with recurring dizziness. She underwent successful myxoma excision at 20 weeks under general anaesthesia and cardiopulmonary bypass. The 6×5 cm myxoma was histologically confirmed as myxoma. Early detection of atrial myxoma in pregnancy is crucial, and a clinician has to consider the diagnosis of left atrial myxoma with mitral valve obstruction as a cause of severe dizziness. Optimal outcomes require multidisciplinary management. In this case, surgery during the second trimester of pregnancy enabled a full-term pregnancy with the patient's and foetal well-being and normal postprocedural echocardiography.

Recognition and management of left atrial dissection during mitral repair.

BACKGROUND: Left atrial dissection (LAtD) is a rare but potentially life-threatening complication of mitral valve surgery. Its management is not well stablished in the literature. However, early recognition through intraoperative TEE and attention to changes in the left atrial free wall during saline leak testing can lead to avoidance of severe complications. CASE PRESENTATION: We report a case of LAtD detected by intraoperative transesophageal echocardiogram (TEE) following mitral valve repair for primary mitral valve regurgitation secondary to degenerative mitral valve disease with MAZE IV procedure for atrial fibrillation. LAtD was noted on TEE as an expanding double density along the wall of the left atrium with a jet originating at the posterior annulus flowing into the LAtD which was repaired. Separation from bypass following LAtD repair was complicated by severe biventricular dysfunction requiring significant inotropic support and placement of an intra-aortic balloon pump (IABP). Patient's post-operative course was further complicated by right sided heart failure requiring placement of a right sided impella which was subsequently removed on POD 4. Patient was discharged home on POD 17. Transthoracic echo at 1 month, 3 months demonstrated resolution of the LAtD. A follow up echo at 4 years showed complete resolution of the LAtD with an intact mitral repair, trace mitral regurgitation, and a mean gradient across the repair of 3 mm Hg. CONCLUSIONS: Left atrial dissection is a rare but serious complication of mitral valve surgery. We provide a review of the current literature regarding LAtD, emphasizing the need to consider this complication early during mitral surgery to allow for uncomplicated repair.

SuperMap algorithm: an efficient, safe and accurate modality for mapping and eliminating challenging cardiac arrhythmias.

Even with the development of advanced catheter-based mapping systems, there remain several challenges in the electrophysiological evaluation and elimination of atrial arrhythmias. For instance, atrial tachycardias with irregular rates cannot be reliably mapped by systems that require stability in order to sequentially gather data points to be organized thereafter. Separately, these arrhythmias often arise following initial ablation for atrial fibrillation, posing logistic challenges. Here, we present the available literature summarizing the use of a non-contact mapping catheter, the AcQMap catheter, in conjunction with SuperMap, an algorithm that compiles a large number of non-contact data points from multiple catheter positions within the atria. These studies demonstrate the efficiency, safety and accuracy of this technology.

Irregular heart rhythms (arrhythmias) are often treatable with medications, but sometimes require expert evaluation in a cardiac electrophysiology laboratory. They are often studied and treated using thin, flexible catheters which enter the body through blood vessels in the leg and reach the internal walls of the heart. Time, expertise and specialized equipment are necessary to identify characteristics specific to each patient's arrhythmia. For each arrhythmia, a unique electrical blueprint is created before trying to eliminate it. The fleeting nature of certain arrhythmias can make it difficult to generate these blueprints, and many take a lot of time to accurately identify, leading to procedural challenges. Here we evaluate studies discussing the use of a new catheter (AcQMap) and its accompanying strategy for identifying arrhythmias. Unlike traditional catheters that require direct contact with the internal walls of the heart, the AcQMap catheter floats within these blood-filled chambers and does not touch the walls when obtaining data points. Instead, using ultrasound waves and electrical signals, it can generate data points to create blueprints. This technology also uses a new algorithm that enables the catheter to move freely within the heart, obtaining numerous data points and grouping them together to create maps efficiently and safely, even for fleeting or challenging arrhythmias.

[Efficacy of Pulmonary Vein Isolation in the Surgical Treatment of Atrial Fiburillation].

BACKGROUND: Maze surgery is often performed for atrial fibrillation during cardiac surgery, and a certain number of therapeutic effects are observed. However, the effectiveness of pulmonary vein isolation (PVI) remains unclear. METHODS: 329 arrhythmia surgeries was performed between 2012 and 2021. The patients were divided into three groups:paroxysmal atrial fibrillation (PAf) group, persistent atrial fibrillation group (PerAf), and long persistent atrial fibrillation( LongPerAf) group. In the PVI and maze groups, postoperative sinus rhythm rate and the rate of freedom from Af recurrence were compared. RESULTS: In PAf, PerAf cases, there was no difference between PVI and maze groups in the rate of freedom from recurrent Af and postoperative sinus rhythm rate. In LongPerAf cases, the rates of freedom from recurrent Af and postoperative sinus rhythm were significantly lower in the PVI group. CONCLUSION: PVI was considered effective in patients with atrial fibrillation of less than one year duration due to the simplicity of the procedure and low complications.

[Long-term Outcomes of the Maze Procedure Omitting the Ablation Line to The Superior Vena Cava].

OBJECTIVE: In an effort to avoid postoperative sick sinus syndrome( SSS), we omit the ablation line to the superior vena cava( SVC) in the Cox-mazeⅢ lesion set. We report the long-term outcomes, including the freedom from SSS. METHODS: We studied 102 patients who underwent bi-atrial maze procedure for persistent atrial fibrillation (Af) from 2009 through 2023. Bipolar radio frequency ablation or cryoablation was used except for right-side atriotomy and right atriotomy. Cryoablation was used for atrioventricular annulus. The patient age was 68±9.4. Duration of Af was 3.4±6.5 years (unknown 9 cases). The amplitude of f-wave in V1 was 0.182±0.095 mV and it was<0.1 mV in 19 (18.6%). Diameter of the left atrium was 50±8.9 mm, and left atrial volume index was 89±37 ml/m2. Ninety-one (89.2%) patients underwent concomitant mitral valve surgery. RESULTS: Survival rate was 99% at 1 year and 96% at 5 years. Freedom from Af was 92% at 1 year and 88% at 5 years. Freedom from permanent pacemaker implantation (PPI) was 87% at 1 year and 83% at 5 years. CONCLUSIONS: Defibrillation rate and the incidence of PPI was comparable to those in previous reports after standard Cox-mazeⅢ. SSS after maze for persistent Af seem due to patient.

[Early Outcomes and Indications for Surgical Intervention of Preoperative Atrial Fibrillation].

BACKGROUND: This study investigates short-term outcomes following surgical interventions for atrial fibrillation (Af), including the Cox-maze Ⅳ procedure (maze procedure) and pulmonary vein isolation (PVI), performed concurrently with other cardiac surgeries. Additionally, we aim to determine the indications for surgical intervention for Af. METHOD: We retrospectively studied a total of 1,580 patients, out of which 274 had preoperative Af, that underwent cardiac surgery between January 2015 and April 2023. Patients who underwent emergency surgery, died in the hospital postoperatively, or received pacemaker implantation were excluded. Patients were first divided into two groups:the intervention group (n=135, 53.6%) and the non-intervention group( n=117, 46.4%), further categorized by whether they were in sinus rhythm at discharge. The intervention group was then subdivided into the maze procedure group( n=54), and the PVI group (n=76). RESULTS: Within the maze procedure group, significant differences were observed between the sinus rhythm and non-sinus rhythm groups in terms of age, preoperative Af duration, and aortic valve intervention status. In the PVI group, patients with persistent Af, longer preoperative Af duration, and larger left atrium diameter( LAD) were less likely to return to sinus rhythm. Smaller LAD was also a significant factor for returning to sinus rhythm in the non-intervention group. Multivariate analysis for all patients revealed that an LAD smaller than 50 mm was the strongest predictor for returning to sinus rhythm post operation( p<0.01). CONCLUSION: For patients with persistent Af, the maze procedure is favored over PVI as a surgical intervention. When LAD exceeds 50 mm, the likelihood of returning to sinus rhythm is diminished.

[Modification of Maze Procedure in Nippon Medical School:Striving Towards Restoration of Sinus Rhythm with Physiological Activation of Atria].

Atrial fibrillation surgery is beneficial for restoring sinus rhythm and maintaining the physiological atrial contraction to prevent left atrial thrombus formation. The radial procedure, a good alternative to the maze procedure, has been performed at Nippon Medical School;it was designed to maintain physiological atrial excitation and blood flow. The design reduces the incision line and avoids conduction delay in the atrium through the use of ablation devices and intraoperative mapping of atrial excitation patterns. In addition, it preserves sinus node function and cardiac conduction pathway;this could prevent postoperative pacemaker implantation.

[Development of a Novel Simple Electrophysiological Study During Atrial Fibrillation Surgery:the Methods of Identifying AFs Where Pulmonary Vein Isolation is Effective].

BACKGROUND & AIM: Surgical procedure for chronic atrial tiburillation (Af) associated with organic cardiac disease is still superior, but atrial potential mapping has rarely been performed for these patients. An epicardial mapping is necessary to elucidate the electrophysiology of Af as a disease, and to verify whether interventions are correctly performed to establish surgical treatment. We report the development of a new method that enables simple and immediate intraoperative decisions electrophysiologically. METHODS & RESULTS: To realize real-time epi-atrial mapping, we planned to apply the mapping system (ExTRa Mapping System), which is already clinically applied during catheter ablation in Japan, for potential acquisition analysis. We developed an epicardial probe (20-point spiral electrode, 25 mm in diameter) that is compatible with the ExTRa mapping system. Using these electrodes, 5-second continuous recordings were made at 12 right atrial (RA) and 7 left atrial (LA) areas, covering the entire atrial surface, to confirm the existence and distribution of multiple wavelets and their central rotors (Ro). Both atria were mapped in 3 patients with chronic Af with mitral valve disease who underwent open heart surgery through a median sternotomy (mean age 73 years, 3 males). Ro was clearly expressed on the monitor display which can be observed by operator in real time. DISCUSSION & CONCLUSION: The system we have developed made it possible to observe Ro, which electrically characterize chronic Af, including their distribution in real time. The development of electrophysiologically- supported theoretical Af surgery can be expected through the accumulation of cases, detailed potential analysis, and verification of the placement of the isolation line and surgical results.