Impact of polypharmacy on 3-year mortality in patients with heart failure: a retrospective study.

BACKGROUND: Guideline-directed medical therapy (GDMT) is important in heart failure management; however, polypharmacy itself may impact heart failure. Although measures against polypharmacy are needed, current discussion on unilateral drug tapering (including the drugs that should be tapered) is insufficient. In this study, we investigated the relationship between the number of prescribed GDMT drugs and prognosis in patients with heart failure. METHODS: In this single-centre retrospective study, 3,146 eligible patients with heart failure were included and divided into four groups based on the median number of prescribed GDMT drugs and the median number of drugs not included in the GDMT (ni-GDMT) at the time of hospital discharge. The definition of GDMT was based on various Japanese guidelines. The primary outcome was all-cause mortality within 3 years of hospital discharge. RESULTS: A total of 252 deaths were observed during the 3-year follow-up period. Kaplan-Meier analysis revealed that groups with GDMT drug count ≥ 5 and ni-GDMT drug count < 4 had the lowest mortality, and those with GDMT drug count < 5 and ni-GDMT drug count ≥ 4 had the highest mortality (log-rank, P < 0.001). Cox regression analysis revealed a significant association between ni-GDMT drug count and all-cause mortality, even after adjustment for number of GDMT medications, age, male, left ventricular ejection function < 40%, hemoglobin, albumin levels, and estimated glomerular filtration rate [HR = 1.06 (95% CI: 1.01-1.11), P = 0.020]. Conversely, the GDMT drug count was not associated with increased mortality rates. CONCLUSIONS: The ni-GDMT drug count was significantly associated with 3-year mortality in patients with heart failure. Conversely, the GDMT drug count did not worsen the prognosis. Polypharmacy measures should consider ni-GDMT drug quantity to improve the prognosis and outcomes in patients with heart failure.

Ten-year trends in non-surgical patients requiring intensive care: Long-term prognostic differences by year of admission.

BACKGROUND: The aim of the present study is to elucidate prognostic impact of temporal trends of non-surgical patients requiring intensive care over a 10-year period. METHODS AND RESULTS: A total of 4276 non-surgical patients requiring intensive care from 2012 to 2021 were enrolled. Patients' backgrounds, in-hospital management, and prognoses were compared between five groups [2012-2013 (n = 825), 2014-2015 (n = 784), 2016-2017 (n = 864), 2018-2019 (n = 939), and 2020-2021 (n = 867)]. During the study period, mean age significantly increased from 69 years in 2012-2013 to 72 years in 2020-2021. Mean Acute Physiology and Chronic Health Evaluation scores significantly increased from 10 points in 2012-2013 to 12 points in 2020-2021. The median duration of intensive care unit stays increased from 3 to 4 days. Kaplan-Meier survival curve analysis showed that survival rates during 30- and 365-days were significantly lower in 2020-2021 than in 2012-2013, but it was not significantly different by a Cox proportional hazards regression model in 30 days. A Cox proportional hazards regression model revealed that the risks of 365-day all-cause death were significantly higher in patients enrolled in 2016-2017 (HR: 1.324, 95 % CI: 1.042-1.680, p = 0.021), in 2018-2019 (HR: 1.329, 95 % CI: 1.044-1.691, p = 0.021), and in 2020-2021 (HR: 1.409, 95 % CI: 1.115-1.779, p = 0.004). CONCLUSION: The condition of patients requiring intensive care is becoming more critical year by year, leading to poorer long-term prognoses despite improvements in treatment strategies. These findings emphasize the importance of additional care management after admission into non-surgical intensive care units, particularly for the aging society of Japan.

Time Course of Left Ventricular Strain Assessment via Cardiovascular Magnetic Resonance Myocardial Feature Tracking in Takotsubo Syndrome.

Background: Although takotsubo syndrome (TTS) is characterized by transient systolic dysfunction of the left ventricle (LV), the time course and mechanism of LV function recovery remain elusive. The aim of this study is to evaluate cardiac functional recovery in TTS via serial cardiac magnetic resonance feature tracking (CMR-FT). Methods: In this Japanese multicenter registry, patients with newly diagnosed TTS were prospectively enrolled. In patients who underwent serial cardiovascular magnetic resonance (CMR) imaging at 1 month and 1 year after the onset, CMR-FT was performed to determine the global circumferential strain (GCS), global radial strain (GRS) and global longitudinal strain (GLS). We compared LV ejection fraction, GCS, GRS and GLS at 1 month and 1 year after the onset of TTS. Results: Eighteen patients underwent CMR imaging in one month and one year after the onset in the present study. LV ejection fraction had already normalized at 1 month after the onset, with no significant difference between 1 month and 1 year (55.8 ± 9.2% vs. 58.9 ± 7.3%, p = 0.09). CMR-FT demonstrated significant improvement in GCS from 1 month to 1 year (-16.7 ± 3.4% vs. -18.5 ± 3.2%, p < 0.01), while there was no significant difference in GRS and GLS between 1 month and year (GRS: 59.6 ± 24.2% vs. 59.4 ± 17.3%, p = 0.95, GLS: -12.8 ± 5.9% vs. -13.8 ± 4.9%, p = 0.42). Conclusions: Serial CMR-FT analysis revealed delayed improvement of GCS compared to GRS and GLS despite of rapid recovery of LV ejection fraction. CMR-FT can detect subtle impairment of LV systolic function during the recovery process in patients with TTS.

Late Kidney Injury After Admission to Intensive Care Unit for Acute Heart Failure.

Late kidney injury (LKI) in patients with acute heart failure (AHF) requiring intensive care is poorly understood.We analyzed 821 patients with AHF who required intensive care. We defined LKI based on the ratio of the creatinine level 1 year after admission for AHF to the baseline creatinine level. The patients were categorized into 4 groups based on this ratio: no-LKI (< 1.5, n = 509), Class R (risk; ≥ 1.5, n = 214), Class I (injury; ≥ 2.0, n = 78), and Class F (failure; ≥ 3.0, n = 20). Median follow-up after admission for AHF was 385 (346-426) days. Multivariate logistic regression analysis revealed that acute kidney injury (AKI) during hospitalization (Class R, odds ratio [OR]: 1.710, 95% confidence interval [CI]: 1.138-2.571, P = 0.010; Class I, OR: 6.744, 95% CI: 3.739-12.163, P < 0.001; and Class F, OR: 9.259, 95% CI: 4.078-18.400, P < 0.001) was independently associated with LKI. Multivariate Cox regression analysis showed that LKI was an independent predictor of 3-year all-cause death after final follow-up (hazard ratio: 1.545, 95% CI: 1.099-2.172, P = 0.012). The rate of all-cause death was significantly lower in the no-AKI/no-LKI group than in the no-AKI/LKI group (P = 0.048) and in the AKI/no-LKI group than in the AKI/LKI group (P = 0.017).The incidence of LKI was influenced by the presence of AKI during hospitalization, and was associated with poor outcomes within 3 years of final follow-up. In the absence of LKI, AKI during hospitalization for AHF was not associated with a poor outcome.

Predicting heart failure symptoms from the apnoea-hypopnoea index determined by full- night polysomnography.

AIMS: Sleep-disordered breathing (SDB) is closely related to cardiovascular diseases. The higher the apnoea-hypopnoea index (AHI), the higher the prevalence of cardiovascular diseases. Despite these findings suggesting a close link between SDB and heart failure, the relationship between the severity of SDB and the onset of heart failure symptoms in individuals without apparent heart failure symptoms (Heart Failure Stage A + B) remains poorly understood. METHODS AND RESULTS: Between December 2010 and June 2017, we conducted full-night polysomnography (PSG) at the Nippon Medical School Chiba Hokusoh Hospital, extracting patients who were at risk of heart failure (Stage A or B in the Heart Failure Guidelines). Using a median cut-off of AHI ≥ 41.6 events/hour, we divided the patients into two groups and examined the composite endpoint of all-cause mortality plus hospitalization due to heart failure as the primary endpoint. We included 230 patients (mean age 63.0 ± 12.5 years, 78.3% males) meeting the selection criteria. When comparing the two groups, those with AHI < 41.6 events/hour (L group, n = 115) and those with AHI ≥ 41.6 events/hour (H group, n = 115), the H group had higher body mass index and higher serum triglyceride, and lower the frequency of acute coronary syndrome and lower estimated glomerular filtration rate than did the L group, but no other patient characteristics differed significantly. The H group had a significantly higher incidence of the composite endpoint than did the L group (10.6% vs. 2.6%, P = 0.027). Factors associated with the composite endpoint were identified through multivariate analyses, with AHI, haemoglobin, and left atrial dimension emerging as significant factors (hazard ratio [HR] = 1.02, 95% confidence interval [CI] = 1.00-1.04, P = 0.024; HR = 0.71, 95% CI = 0.54-0.94, P = 0.017; and HR = 1.10, 95% CI = 1.03-1.18, P = 0.006, respectively). Conversely, the minimum SpO2 during PSG (<80%) was not associated with the composite endpoint. CONCLUSIONS: In patients with SDB who are at risk of heart failure, severe SDB is associated with a high risk of all-cause mortality and the development of heart failure. Additionally, combining cardiac echocardiography and PSG data may improve risk stratification, offering potential assistance for early intervention. Further examination with a validation cohort is necessary.

Prognostic impact of plasma volume status during hospital admission in patients with acute decompensated heart failure.

AIMS: Plasma volume status (PVS), a measure of plasma volume, has been evaluated as a prognostic marker for chronic heart failure. Although the prognostic value of PVS has been reported, its significance in patients with acute decompensated heart failure (ADHF) admitted to the cardiovascular intensive care unit (CICU) remains unclear. In this study, we examined the relationship between PVS and long-term mortality in patients with ADHF admitted to the CICU. METHODS: Between January 2018 and December 2020, 363 consecutive patients with ADHF were admitted to the Nippon Medical School Hospital CICU. Of the 363 patients, 206 (mean age, 74.9 ± 12.9 years; men, 64.6%) were enrolled in this study. Patients who received red blood cell transfusions, underwent dialysis, were discharged from the CICU or died in the hospital were excluded from the study. We measured the PVS of the patients at admission, transfer to the general ward (GW) and discharge using the Kaplan-Hakim formula. The patients were assigned to four groups according to the quartiles of their PVS measured at each of the three abovementioned timepoints. We examined the association between PVS and all-cause mortality during the observation period (1134 days). The primary endpoint of this study was all-cause mortality. RESULTS: The Kaplan-Meier analysis showed that the high PVS group had a significantly higher mortality rate at admission, transfer to the GW and discharge than the other groups (log-rank test: P = 0.016, P = 0.005 and P < 0.001, respectively). Univariate Cox regression analysis showed that age, body mass index, history of heart failure, use of beta-blockers, albumin level, blood urea nitrogen level, N-terminal pro-brain natriuretic peptide level and left ventricular ejection fraction were significantly different among the PVS groups and thus were not significant prognostic factors for ADHF. Furthermore, the multivariate analysis revealed that PVS at discharge [hazard ratio (HR) = 1.06 (1.00-1.12), P = 0.048] was an independent poor prognostic factor for ADHF. CONCLUSIONS: This study highlights the effect of PVS measured at different timepoints on the prognoses of ADHF patients. Regular assessment of PVS, particularly at discharge, is crucial for optimising patient management and achieving favourable outcomes in cases of ADHF.

Reinforcement of pimobendan with guideline-directed medical therapy may reduce the rehospitalization rates in patients with heart failure: retrospective cohort study.

BACKGROUND: Pimobendan reportedly improves the subjective symptoms of heart failure. However, evidence of improved prognosis is lacking. This study aimed to determine whether reinforcing guideline-directed medical therapy (GDMT) improved rehospitalization rates for worsening heart failure in patients administered pimobendan. METHODS: A total of 175 patients with heart failure who were urgently admitted to our hospital for worsening heart failure and who received pimobendan between January 2015 and February 2022 were included. Of the 175 patients, 44 were excluded because of in-hospital death at the time of pimobendan induction. The remaining 131 patients were divided into two groups, the reduced ejection fraction (rEF) (n = 93) and non-rEF (n = 38) groups, and further divided into the GDMT-reinforced and non-reinforced groups. RESULTS: In patients with rEF, the rate of rehospitalization for heart failure was significantly lower in the GDMT-reinforced group than in the non-reinforced group (log-rank test, P = .04). However, the same trend was not observed in the non-rEF group. CONCLUSIONS: Reinforcing GDMT may reduce the heart failure rehospitalization rate in patients with pimobendan administration and rEF. However, multicenter collaborative research is needed. TRIAL REGISTRATION: IRB Approval by the Nippon Medical School Hospital Ethics Committee B-2021-433 (April 10, 2023).

Hepatic function markers as prognostic factors in patients with acute kidney injury undergoing continuous renal replacement therapy.

Acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT), secondary to cardiovascular disease and sepsis, is associated with high in-hospital mortality. Although studies have examined cardiovascular disease and sepsis in AKI, the association between AKI and hepatic functional impairment remains unclear. We hypothesized that hepatic function markers would predict mortality in patients undergoing CRRT. We included 1,899 CRRT patients from a multi-centre database. In Phase 1, participants were classified according to the total bilirubin (T-Bil) levels on the day of, and 3 days after, CRRT initiation: T-Bil < 1.2, 1.2 ≤ T-Bil < 2, and T-Bil ≥ 2 mg/dL. In Phase 2, propensity score matching (PSM) was performed to examine the effect of a T-Bil cutoff of 1.2 mg/dL (supported by the Sequential Organ Failure Assessment score); creating two groups based on a T-Bil cutoff of 1.2 mg/dL 3 days after CRRT initiation. The primary endpoint was total mortality 90 days after CRRT initiation, which was 34.7% (n = 571). In Phase 1, the T-Bil, aspartate transaminase (AST), alanine transaminase (ALT), and AST/ALT (De Ritis ratio) levels at CRRT initiation were not associated with the prognosis, while T-Bil, AST, and the De Ritis ratio 3 days after CRRT initiation were independent factors. In Phase 2, T-Bil ≥1.2 mg/dL on day 3 was a significant independent prognostic factor, even after PSM [hazard ratio: 2.41 (95% CI; 1.84-3.17), p < 0.001]. T-Bil ≥1.2 mg/dL 3 days after CRRT initiation predicted 90-day mortality. Changes in hepatic function markers in acute renal failure may enable stratification of high-risk patients.

Exploring Possible Links: Thigh Muscle Mass, Apolipoproteins, and Glucose Metabolism in Peripheral Artery Disease-Insights from a Pilot Sub-Study following Endovascular Treatment.

Peripheral artery disease (PAD) compromises walking and physical activity, which results in further loss of skeletal muscle. The cross-sectional area of the thigh muscle has been shown to be correlated with systemic skeletal muscle volume. In our previous pilot study, we observed an increase in thigh muscle mass following endovascular treatment (EVT) in patients with proximal vascular lesions affecting the aortoiliac and femoropopliteal arteries. Considering the potential interactions between skeletal muscle, lipid profile, and glucose metabolism, we aimed to investigate the relationship between thigh muscle mass and apolipoproteins as well as glucose metabolism in PAD patients undergoing EVT. This study is a prespecified sub-study conducted as part of a pilot study. We prospectively enrolled 22 symptomatic patients with peripheral artery disease (PAD) and above-the-knee lesions, specifically involving the blood vessels supplying the thigh muscle. The mid-thigh muscle area was measured with computed tomography before and 6 months after undergoing EVT. Concurrently, we measured levels of apolipoproteins A1 (Apo A1) and B (Apo B), fasting blood glucose, 2 h post-load blood glucose (using a 75 g oral glucose tolerance test), and glycated hemoglobin A1c (HbA1c). Changes in thigh muscle area (delta muscle area: 2.5 ± 8.1 cm2) did not show significant correlations with changes in Apo A1, Apo B, fasting glucose, 2 h post-oral glucose tolerance test blood glucose, HbA1c, or Rutherford classification. However, among patients who experienced an increase in thigh muscle area following EVT (delta muscle area: 8.41 ± 5.93 cm2), there was a significant increase in Apo A1 (pre: 121.8 ± 15.1 mg/dL, 6 months: 136.5 ± 19.5 mg/dL, p < 0.001), while Apo B remained unchanged (pre: 76.4 ± 19.2 mg/dL, 6 months: 80.5 ± 4.9 mg/dL). Additionally, post-oral glucose tolerance test 2 h blood glucose levels showed a decrease (pre: 189.7 ± 67.5 mg/dL, 6 months: 170.6 ± 69.7 mg/dL, p = 0.075). Patients who exhibited an increase in thigh muscle area demonstrated more favorable metabolic changes compared to those with a decrease in thigh muscle area (delta muscle area: -4.67 ± 2.41 cm2). This pilot sub-study provides insights into the effects of EVT on thigh muscle, apolipoproteins, and glucose metabolism in patients with PAD and above-the-knee lesions. Further studies are warranted to validate these findings and establish their clinical significance. The trial was registered on the University Hospital Medical Information Network Clinical Trials Registry (UMIN000047534).

Fractional excretion of urea nitrogen can identify true worsening renal function in patients with heart failure.

AIMS: Fractional excretion of urea nitrogen (FEUN), used to differentiate the cause of acute kidney injury, has emerged as a useful fluid index in patients with heart failure (HF). We hypothesized that FEUN could be useful in identifying worsening renal function (WRF) associated with poor outcomes in patients with acute HF (AHF). METHODS AND RESULTS: Overall, 1103 patients with AHF (median age, 78 years; male proportion, 60%) were categorized into six groups according to the presence of WRF and FEUN values (low, ≤32.1%; medium, >32.1% and ≤38.0%; and high, >38.0%) at discharge. WRF was defined as an increase of ≥0.3 mg/dL in the serum creatinine level from admission to discharge. FEUN was calculated by the following formula: (urinary urea × serum creatinine) × 100/(serum urea × urinary creatinine). The cut-off values for low, medium, and high FEUN were based on a previous study. The primary outcome of this study was HF readmission after hospital discharge. During the 1 year follow-up, 170 HF readmissions occurred. Kaplan-Meier analysis revealed significantly higher HF readmission rates in patients with WRF than in those without WRF (log-rank test, P < 0.001). Additionally, among patients with WRF, HF readmission rates were lowest in those with medium FEUN values, followed by those with low FEUN values and those with high FEUN values. On multivariable analysis, the presence of WRF with low or high FEUN values was independently associated with increased HF readmission, as compared with the absence of WRF with medium FEUN values. Notably, no association was noted between WRF with medium FEUN values and HF readmission. CONCLUSIONS: The prognostic impact of WRF was significantly mediated by the FEUN values and was associated with worse outcomes only when the FEUN values were either low or high. Our study suggests that FEUN can identify prognostically relevant WRF in patients with AHF.

Clinical Significance of the Triglyceride-Glucose Index in Patients Requiring Nonsurgical Intensive Care.

The evaluation of triglyceride-glucose (TyG) index has not been sufficient in patients requiring nonsurgical intensive care.A total of 3,906 patients who required intensive care were enrolled. We computed the TyG index using the value on admission by the following formula: ln [triglyceride (mg/dL) × glucose (mg/dL) /2]. Patients were divided into three groups according to the TyG index quartiles: low (quartile 1 [Q1]; TyG index ≤ 8.493, n = 977), middle (Q2/Q3; 8.494 ≤ TyG index ≤ 9.536, n = 1,953), and high (Q4; TyG index > 9.537, n = 976). The median (interquartile range) TyG index was 9.00 (8.50-9.54); acute coronary syndrome (ACS) had the highest TyG index among all etiologies at 9.12 (8.60-9.68). A multivariate logistic regression model showed that ACS (odds ratio [OR], 2.133; 95% confidence interval [CI], 1.783-2.552) were independently correlated with high TyG index. A Cox proportional hazards regression model revealed that, in ACS, the Q2/Q3 and Q4 groups were independent predictors of 30-day all-cause mortality (hazard ratio [HR], 1.778; 95% CI, 1.014-3.118; HR, 2.986; 95% CI, 1.680-5.308; respectively) and that in acute heart failure [AHF], the Q4 group was a converse independent predictor of 30-day all-cause mortality (HR, 0.488; 95% CI, 0.241-0.988).High TyG index was linked to ACS and negative outcomes in the ACS group; in contrast, low TyG index was associated with adverse outcomes in the AHF group.

Impact of Red Blood Cell Transfusion on Subsequent Cardiovascular Events in Patients with Acute Heart Failure and Anemia.

Red blood cell (RBC) transfusion therapy is often performed in patients with acute heart failure (AHF) and anemia; however, its impact on subsequent cardiovascular events is unclear. We examined whether RBC transfusion influences major adverse cardiovascular events (MACE) after discharge in patients with AHF and anemia.We classified patients with AHF and anemia (nadir hemoglobin level < 10 g/dL) according to whether they received RBC transfusion during hospitalization. The endpoint was MACE (composite of all-cause death, non-fatal acute coronary syndrome/stroke, or heart failure readmission) 180 days after discharge. For survival analysis, we used propensity score matching analysis with the log-rank test. As sensitivity analysis, we performed inverse probability weighting analysis and multivariable Cox regression analysis.Among 448 patients with AHF and anemia (median age, 81 years; male, 55%), 155 received RBC transfusion and 293 did not. The transfused patients had worse clinical features than the non-transfused patients, with lower levels of nadir hemoglobin and serum albumin and a lower estimated glomerular filtration rate. In the propensity-matched cohort of 87 pairs, there was no significant difference in the MACE-free survival rate between the 2 groups (transfused, 73.8% vs. non-transfused, 65.3%; P = 0.317). This result was consistent in the inverse probability weighting analysis (transfused, 76.0% vs. non-transfused, 68.7%; P = 0.512), and RBC transfusion was not significantly associated with post-discharge MACE in the multivariable Cox regression analysis (adjusted hazard ratio: 1.468, 95% confidence interval: 0.976-2.207; P = 0.065).In conclusion, this study suggests that RBC transfusions for anemia may not improve clinical outcomes in patients with AHF.

Clinical Background and Coronary Artery Lesions Characteristics in Japanese Patients With Acute Coronary Syndrome Suffering Major Bleeding.

Background: Although the clinical factors that predict major bleeding in Western patients with acute coronary syndrome (ACS) are becoming elucidated, they have not been fully investigated, especially coronary lesion characteristics, in a Japanese population. Methods and Results: ACS patients (n=1,840) were divided into a "bleeding group" and a "no-bleeding group," according to whether they had major bleeding during the 2-year follow-up period, to investigate the prognostic effect of bleeding and the predictive factors of bleeding. Among them, patients who underwent primary percutaneous coronary intervention with optical coherence tomography (OCT) guidance (n=958) were examined to identify the effect of coronary lesion characteristics on bleeding. Of the 1,840 enrolled patients, 124 (6.7%) experienced major bleeding during the 2-year follow-up period. Incidence of cardiovascular death during the 2-year follow-up period was significantly higher among patients with major bleeding (26.4% vs. 8.5%, P=0.001). OCT examination showed that disrupted fibrous cap (DFC: 68% vs. 48%, P=0.014) and calcified plaque (63% vs. 42%, P=0.011) were more prevalent in the bleeding group. DFC was a predictor of major bleeding in the multivariate Cox proportional hazards analyses (hazard ratio 2.135 [95% confidence interval 1.070-4.263], P<0.001). Conclusions: ACS patients with major bleeding had poorer cardiac outcomes. Advanced atherosclerosis at the culprit lesion influences the higher incidence of major bleeding in ACS patients.

Electrophysiological and Histopathological Characteristics of Ventricular Tachycardia Associated With Primary Cardiac Tumors.

BACKGROUND: Ventricular tachycardia (VT) associated with primary cardiac tumors (PCTs) originating from the ventricles is rare, but lethal, in young patients. OBJECTIVES: This study aimed to clarify the mechanisms underlying primary cardiac tumor-related ventricular tachycardia (PCT-VT) and establish a therapeutic strategy for this form of VT. METHODS: Among 67 patients who underwent surgery for VT at our institute between 1981 and 2020, 4 patients aged 1 to 34 years, including 3 males, showed PCT-VT (fibroma, 2; lipoma, 1; and hamartoma, 1), which was investigated using a combination of intraoperative electroanatomical mapping and histopathological studies. RESULTS: All 4 patients developed electrical storms of sustained VTs refractory to multiple drugs and repetitive endocardial ablations. The VT mechanism was re-entry, and intraoperative electroanatomical mapping showed a centrifugal activation pattern originating from the border between the tumor and healthy myocardium, where fractionated potentials were detected during sinus rhythm. Histopathological studies of serial sections of specimens acquired from these areas revealed tumor infiltration into the surrounding myocardium with cell disorganization, exhibiting myocardial disarray. Several myocardia entrapped in the tumor edges contributed to the development and sustainment of re-entrant VT activation. In the 2 patients in whom complete resection was unfeasible, encircling cryoablation to entirely isolate the unresectable tumor was effective in suppressing VT occurrence. CONCLUSIONS: The mechanism underlying PCT-VT involves re-entry localized at the tumor edges. Myocardial disarray associated with tumor infiltration is a substrate for this form of VT. Cryoablation along the border between the tumor and myocardium is a promising therapeutic option for unresectable PCT-VT.