The Balance of CD8-Positive T Cells and PD-L1 Expression in the Myocardium Predicts Prognosis in Lymphocytic Fulminant Myocarditis.

INTRODUCTION: The clinical significance and prognostic value of T cell involvement and programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) have not been established in lymphocytic fulminant myocarditis (FM). We investigated the prognostic impact of the number of CD4+, CD8+, FoxP3+, and PD-1+ T cells, as well as PD-L1 expression, in cardiomyocytes in lymphocytic FM. METHODS: This is a single-center observational cohort study. Myocardial tissue was obtained from 16 consecutive patients at lymphocytic FM onset. The median follow-up was 140 days. Cardiac events were defined as a composite of cardiac death and left ventricular-assist device implantation. CD4, CD8, FoxP3, PD-1, and PD-L1 immunostaining were performed on myocardial specimens. RESULTS: The median age of the patients was 52 years (seven men and nine women). There was no significant difference in the number of CD4+ cells. The number of CD8+ cells and the CD8+/CD4+ T cell ratio were higher in the cardiac event group (Event+) than in the group without cardiac events (Event-) (p = 0.048 and p = 0.022, respectively). The number of FoxP3+ T cells was higher in the Event+ group (p = 0.049). Although there was no difference in the number of PD-1+ cells, cardiomyocyte PD-L1 expression was higher in the Event+ group (p = 0.112). Event-free survival was worse in the group with a high CD8+ cell count (p = 0.012) and high PD-L1 expression (p = 0.049). When divided into three groups based on the number of CD8+ cells and PD-L1 expression (CD8highPD-L1high [n = 8], CD8lowPD-L1high [n = 1], and CD8lowPD-L1low [n = 7]), the CD8highPD-L1high group demonstrated the worst event-free survival, while the CD8lowPD-L1high group had a favorable prognosis without cardiac events (p = 0.041). CONCLUSION: High myocardial expression of CD8+ T cells and PD-L1 may predict a poor prognosis in lymphocytic FM.

Increased risk of purge system malfunction after Impella 5.0 replacement: a case series.

The Impella 5.0 is an axial-flow percutaneous ventricular assist device used in patients with cardiogenic shock. Although the recommended period of use is 10 days or less, weaning can be delayed because of ongoing hemodynamic instability. In clinical practice, this device sometimes malfunctions during long-term management with heparin and must be replaced; however, the relationship between the duration of support with the initial and replacement Impella 5.0 and the changes in value of the purge system has not been fully elucidated. From July 2018 to May 2021, Impella 5.0 was implanted and used for more than 10 days in 11 patients at our institution. Four patients required Impella replacement because of device malfunction and the second Impella had purge system malfunction in all cases. The second Impella was used for a significantly shorter time than the first Impella (p = 0016). We calculated the ratio of purge pressure to purge flow rate and found that the ratio exceeded 50 mm Hg/mL/h in all cases with purge system malfunction. In conclusion, it is important to construct a treatment strategy considering the duration of use, because the risk of purge system malfunction is high after replaced Impella 5.0.

Clinical Effect of Pulmonary Artery Diameter/Ascending Aorta Diameter Ratio on Left Ventricular Reverse Remodeling in Patients With Dilated Cardiomyopathy.

BACKGROUND: Many patients with dilated cardiomyopathy (DCM) progress to heart failure (HF), although some demonstrate left ventricular (LV) reverse remodeling (LVRR), which is associated with better outcomes. The pulmonary artery diameter (PAD) to ascending aortic diameter (AoD) ratio has been used as a prognostic predictor in patients with HF, although this tool's usefulness in predicting LVRR remains unknown.Methods and Results: Data from a prospective observational study of 211 patients diagnosed in 2000-2020 with DCM were retrospectively analyzed. Sixty-nine patients with New York Heart Association class I or II HF were included. LVRR was observed in 23 patients (33.3%). The mean LV ejection fraction (29%) and LV end-diastolic dimension (64.5 mm) were similar in patients with and without LVRR. The PAD/AoD ratio was significantly lower in patients with LVRR than those without (81.4% vs. 92.4%, respectively; P=0.003). The optimal PAD/AoD cut-off value for detecting LVRR was 0.9 according to the receiver operating characteristic curve analysis. Multivariate analysis identified a PAD/AoD ratio ≥0.9 as an independent predictor of presence/absence of LVRR. Cardiac events were significantly more common in patients with a PAD/AoD ratio ≥0.9 than those with a ratio <0.9, after a median follow up of 2.5 years (log-rank, P=0.007). CONCLUSIONS: The PAD/AoD ratio can predict LVRR in patients with DCM.

Splenic size as an indicator of hemodynamics and prognosis in patients with heart failure.

The spleen is an important immune organ that releases erythrocytes and monocytes and destroys aged platelets. It also reserves 20-30% of the total blood volume, and its size decreases in hypovolemic shock. However, the clinical significance of splenic size in patients with heart failure (HF) remains unclear. We retrospectively analyzed the data of 206 patients with clinically stable HF gathered between January 2001 and August 2020 and recorded in a single-center registry. All patients underwent right heart catheterization and computed tomography (CT). Splenic size was measured using CT volumetry. The primary outcomes were composite cardiac events occurring for the first time during follow-up, namely, cardiac death and hospitalization for worsening HF. The median splenic volume and splenic volume index (SVI) were 118.0 mL and 68.9 mL/m2, respectively. SVI was positively correlated with cardiac output (r = 0.269, P < 0.001) and stroke volume (r = 0.228, P = 0.002), and negatively correlated with systemic vascular resistance (r = - 0.302, P < 0.001). Seventy cardiac events occurred, and the optimal receiver operating characteristic curve SVI cutoff value for predicting cardiac events was 68.9 mL/m2. The median blood adrenaline concentration was higher in the low-SVI group than the high-SVI group (0.039 ng/mL vs. 0.026 ng/mL, respectively; P = 0.004), and the low-SVI group experienced more cardiac events (log-rank test, P < 0.001). Multivariate Cox proportional hazards regression revealed that a low SVI was an independent predictor of cardiac events, even when adjusted for the validated HF risk score, blood-brain natriuretic peptide concentration, blood catecholamine concentrations, and hemodynamic parameters. Splenic size reflects hemodynamics, including systemic circulating blood volume status and sympathetic nerve activity, and is associated with HF prognosis.

Prognostic value of malnutrition evaluated using the Global Leadership Initiative on Malnutrition criteria and its association with psoas muscle volume in non-ischemic dilated cardiomyopathy.

Heart failure (HF) is a systemic inflammatory disease that causes hypotrophy and skeletal muscle loss. The Global Leadership Initiative on Malnutrition (GLIM) criteria have been developed as a novel evaluation index for malnutrition, with reported usefulness in HF caused by ischemic heart disease. However, reports on the usefulness of malnutrition evaluated by the GLIM criteria in non-ischemic dilated cardiomyopathy (NIDCM) and its relationship with psoas muscle volume are lacking. We investigated the prognostic value of malnutrition evaluated using the GLIM criteria and its association with psoas muscle volume in patients with NIDCM. We enrolled 139 consecutive patients with NIDCM between December 2000 and June 2020. Malnutrition was evaluated using the GLIM criteria on admission. The median follow-up period was 4.7 years. Cardiac events were defined as a composite of cardiac death, hospitalization for worsening HF, and lethal arrhythmia. Furthermore, we measured the psoas muscle volume using computed tomography volumetry in 48 patients. At baseline, the median age was 50 years, and 132 patients (95.0%) had New York Heart Association functional class I or II HF. The median psoas muscle volume was 460.8 cm3. A total of 26 patients (18.7%) were malnourished according to the GLIM criteria. The Kaplan-Meier survival analysis showed that malnourished patients had more cardiac events than non-malnourished patients (log-rank, P < 0.001). The multivariate Cox proportional hazards regression analysis revealed that GLIM criteria-based malnutrition was an independent determinant of cardiac events (hazard ratio, 2.065; 95% confidence interval, 1.166-3.656; P = 0.014). Psoas muscle volume, which was assessed in a total of 48 patients, was lower in malnourished than in non-malnourished patients (median, 369.0 vs. 502.3 cm3; P = 0.035) and correlated with body mass index (r = 0.441; P = 0.002). Nutritional screening using the GLIM criteria may be useful in predicting future cardiac events in patients with NIDCM, reflecting a potential relationship between malnutrition and a low psoas muscle volume.

Methods for confirming the safety of radiation therapy in patients with left ventricular assist device: a case of extranodal NK/T-cell lymphoma, nasal type.

A left ventricular assist device (LVAD) is a treatment option for patients with end-stage heart failure; however, a certain number of patients on durable LVADs are diagnosed with malignancy. Radiation therapy (RT) for patients with durable LVADs has safety concerns, because RT may interfere with the device. Herein, we report a case of RT during durable LVAD management. A 48-year-old man with a durable LVAD was diagnosed with sinusitis. As his symptoms were resistant to drug therapy, endoscopic sinus surgery was performed, and extranodal NK/T-cell lymphoma, nasal type (ENKL) was pathologically detected. Since RT was the first-line treatment for ENKL, we conducted two types of irradiation experiments to determine whether RT can be safely performed in patients with durable LVADs as follows: (1) assessing the extent of the radiation levels at each site and evaluating device malfunction by irradiating the lesion sites in the patient model with the same protocol as planned, and (2) evaluating device malfunction by directly irradiating the durable LVAD equipment once at the scheduled total dose. The radiation doses at the pump, driveline, system controller, power cable, and power module of the durable LVAD reached 7.86 cGy, 6.34 cGy, 0.66 cGy, 0.38 cGy, and 0.14 cGy, respectively. In both experiments, durable LVAD malfunction or any type of alarm was not observed. We concluded that RT could be safely performed with chemotherapy in this patient and our irradiation experiments can be applied to RT for other malignancies.

Efficacy of Pulmonary Artery Pulsatility Index as a Measure of Right Ventricular Dysfunction in Stable Phase of Dilated Cardiomyopathy.

BACKGROUND: Right ventricular dysfunction (RVD) in the setting of left ventricular (LV) myocardial damage is a major cause of morbidity and mortality, and the pulmonary artery pulsatility index (PAPi) is a novel hemodynamic index shown to predict RVD in advanced heart failure. However, it is unknown whether PAPi can predict the long-term prognosis of dilated cardiomyopathy (DCM) even in the mild to moderate phase. This study aimed to assess the ability of PAPi to stratify DCM patients without severe symptoms.Methods and Results:Between April 2000 and March 2018, a total of 162 DCM patients with stable symptoms were evaluated, including PAPi, and followed up for a median of 4.91 years. The mean age was 50.9±12.6 years and the mean LV ejection fraction (EF) was 30.5±8.3%. When divided into 2 groups based on median value of PAPi (low, L-PAPi [<3.06] and high, H-PAPi [≥3.06]), even though there were no differences in B-type natriuretic peptide or pulmonary vascular resistance, the probability of cardiac event survival was significantly higher in the L-PAP than in the H-PAP group by Kaplan-Meier analysis (P=0.018). Furthermore, Cox's proportional hazard regression analysis revealed that PAPi was an independent predictor of cardiac events (hazard ratio: 0.782, P=0.010). CONCLUSIONS: Even in patients identified with DCM in the mild to moderate phase, PAPi may help stratify DCM and predict cardiac events.

Predictive value of abdominal aortic calcification index for mid-term cardiovascular events in patients with acute coronary syndrome.

The utility of abdominal aortic calcification (AAC) for prediction of cardiovascular events (CVEs) in patients with acute coronary syndrome (ACS) remains to be determined. The aim of this prospective study was to determine the predictive value of the abdominal aortic calcification index (ACI), a semi-quantitative measure of AAC, for CVEs in patients with ACS. We evaluated 314 patients with ACS. All patients underwent successful percutaneous coronary intervention to the culprit coronary vessel without in-hospital adverse events. ACI was calculated on non-contrast computed tomography images. CVEs were defined as a composite of cardiovascular death, ACS recurrence, and stroke. During a median follow-up period of 19.1 months, CVEs occurred in 29 patients (9.2%). Multivariable regression analysis after adjustment for age and gender showed a significantly higher baseline ACI in patients with CVEs than in those without [median (interquartile ranges), 42.1 (25.9-60.2) vs. 20.8 (8.8-38.6) %; P = 0.021]. The cutoff value of ACI for prediction of CVEs, estimated by receiver-operating characteristic analysis, was 29.2%, with sensitivity of 76% and specificity of 64% (area under the curve, 0.69). After adjustment for conventional cardiovascular risk factors, Cox analysis showed high ACI (≥29.2%) to be significantly associated with increased risk of CVEs (P = 0.011; hazard ratio, 1.82). Multivariate analysis identified high ACI as an independent predictor of CVEs (P = 0.012; hazard ratio, 1.80). Stepwise forward selection procedure also showed that high ACI was a significant independent determinant of CVEs (P = 0.004; R2, 0.089). Both net reclassification improvement (0.64; P = 0.001) and integrated discrimination improvement (0.04; P < 0.001) improved significantly after the addition of high ACI to conventional risk factors. Evaluation of ACI using CT seems to provide valuable clinical information for proper assessment of mid-term CVEs in patients with ACS after percutaneous coronary intervention.

Spleen size improvement in advanced heart failure patients using a left ventricular assist device.

The spleen has been recognized as an important organ that holds a reserve of 20% to 30% of the total blood volume. Spleen contraction and splenic volume reduction occur in patients with hypovolemic shock. However, the change in the spleen volume and the association between spleen size and hemodynamic parameters remain unclear in patients with advanced heart failure (HF) who need left ventricular assist device (LVAD) support. This study was performed to investigate the change in spleen size and the relationship between spleen size and hemodynamic parameters before and after LVAD implantation in patients with advanced HF. We enrolled 20 patients with advanced HF on LVAD support. All patients underwent right heart catheterization and computed tomography before and after LVAD implantation. The spleen size was measured by computed tomography volumetry. We excluded patients with a mean right atrial pressure (RAP) of <5 mm Hg because of the possibility of hypovolemia and those with a cardiac index of >2.2 L/min/m2 before LVAD implantation. The splenic volume significantly increased from 160.6 ± 46.9 mL before LVAD implantation to 224.6 ± 73.5 mL after LVAD implantation (P < .001). Before LVAD implantation, there was a significant negative correlation between spleen volume and systemic vascular resistance (SVR). After LVAD implantation, however, there were significant correlations between spleen volume and the cardiac index, RAP, and pulmonary capillary wedge pressure despite the absence of a significant correlation between spleen volume and SVR. Furthermore, one patient developed reworsening HF because of LVAD failure due to pump thrombosis. In this case, the splenic volume was 212 mL before LVAD implantation and increased to 418 mL after LVAD implantation, although it decreased to 227 mL after LVAD failure. The spleen size may change depending on hemodynamics in patients with advanced HF with LVAD support, reflecting sympathetic nerve activity and the systemic volume status.

Aortic insufficiency associated with Impella that required surgical intervention upon implantation of the durable left ventricular assist device.

The Impella is an axial-flow percutaneous ventricular assist device for cardiogenic shock. In this report, we describe two patients who developed aortic insufficiency (AI) associated with Impella and required surgical intervention upon implantation of the durable left ventricular assist device (LVAD). Both patients presented with cardiogenic shock and underwent insertion of Impella 5.0 as a bridge to decision. The cardiac function in these patients did not improve and obtaining approval for heart transplantation required time. They were managed with Impella for 91 and 98 days, respectively. In both cases, moderate AI that was not present before Impella insertion was observed when the Impella was removed. Therefore, we performed aortic valve closure to control the AI during durable LVAD implantation. In patients with durable LVAD implantation, AI may occur and progress after the operation in several cases. Aortic valve surgery is often performed to prevent deterioration of AI, especially in patients with AI before the surgery. Hence, AI is an important complication following Impella device implantation as a bridge to decision. Careful observation of AI is essential when the Impella is removed as the evaluation of AI by echocardiogram during Impella management is cumbersome because of device-generated artifacts.

Usefulness of Plasma Branched-Chain Amino Acid Analysis in Predicting Outcomes of Patients with Nonischemic Dilated Cardiomyopathy.

The metabolism of branched-chain amino acids (BCAAs) is reported to change in heart failure (HF) and correlate with cardiac function. However, the effect of BCAAs on HF remains controversial. We investigate the prognostic value of the plasma BCAA level in nonischemic dilated cardiomyopathy (NIDCM).This study enrolled 39 NIDCM patients, who underwent plasma amino acid (AA) analysis. The ratio of BCAAs to total AAs was calculated. All patients were divided into two groups at the median of BCAA/total AA ratio; high BCAA/total AA group (≥ 0.15, n = 20) and low BCAA/total AA group (< 0.15, n = 19). A cardiac event was defined as a composite of cardiac death, hospitalization for worsening HF, and lethal arrhythmia.The mean age was 51.1 ± 12.3 years and left ventricular ejection fraction (LVEF) was 32.7 ± 10.1%. In the low BCAA/total AA group, the body mass index and the total cholesterol level were lower than in the high BCAA/total AA group. The BCAA/total AA ratio was positively correlated with LVEF (r = 0.35, P = 0.031) and negatively correlated with brain natriuretic peptide (r = -0.37, P = 0.020). The low BCAA/total AA group had a lower cardiac event-free rate (5-year: 100% versus 73%; P = 0.019). In univariate analysis, angiotensin converting enzyme inhibitor or angiotensin II receptor blocker (hazard ratio: 0.045, P = 0.0014), hemoglobin (hazard ratio: 0.49 per 1 g/dL, P = 0.0022), and BCAA/total AA ratio < 0.15 (hazard ratio: not available, P = 0.0066) were major predictors for cardiac events.The BCAA/total AA ratio might be a useful predictor for future cardiac events in patients with NIDCM.

Early Blood Pressure Reduction by Intravenous Vasodilators Is Associated With Acute Kidney Injury in Patients With Hypertensive Acute Decompensated Heart.

BACKGROUND: Intravenous vasodilators are commonly used in patients with hypertensive acute decompensated heart failure (ADHF), but little is known about their optimal use in blood pressure (BP) management to avoid acute kidney injury (AKI). The purpose of this study was to investigate the association between systolic BP (SBP) changes and the incidence of AKI in patients with hypertensive ADHF.Methods and Results:Post-hoc analysis was performed on a prospectively enrolled cohort. We investigated 245 patients with ADHF and SBP >140 mmHg on arrival (mean age, 76 years; 40% female). We defined "SBP-fall" as the maximum percent reduction in SBP 6 h after intravenous treatment. AKI was defined as serum creatinine (SCr) ≥0.3 mg/dL, or urine output <0.5 mL/kg/h (n=66) at 48 h. Mean SBP and SCr levels on arrival were 180 mmHg and 1.21 mg/dL, respectively. Patients with AKI had significantly larger SBP-fall than the others (36.7±15.3% vs. 27.2±15.3%, P<0.0001). Logistic regression analysis showed an odds ratio per 10% SBP-fall for AKI of 1.49 (95% confidence interval 1.29-1.90, P=0.001). SBP-fall was significantly associated with the number of concomitant used intravenous vasodilators (P=0.001). The administration of carperitide was also independently associated with increased incidence of AKI. CONCLUSIONS: Larger SBP-fall from excessive vasodilator use is associated with increased incidence of AKI in patients with hypertensive ADHF.

Impact of Coronary Stent Fracture on Restenotic Neointimal Tissue Characterization After Drug-Eluting Stent Implantation.

Although drug-eluting stents (DESs) reduce the rates of in-stent restenosis (ISR) and subsequent target lesion revascularization, stent fracture (SF) after DES implantation has become an important concern because of its potential association with restenosis and stent thrombosis. We aimed to assess the pathogenic impact of SF on in-stent restenotic neointimal tissue components after DES implantation. We analyzed 43 consecutive patients (14 with SF and 29 without SF) with ISR requiring revascularization after DES implantation between January 2008 and March 2014. For evaluation of in-stent tissue components, integrated backscatter intravascular ultrasound (IB-IVUS) was performed. SF was defined as complete or partial separation of stent segments observed using plain fluoroscopy or intravascular ultrasound. On volumetric IB-IVUS analyses, patients with SF had a significantly higher percentage of lipid tissue volume within the neointima and a significantly lower percentage of fibrous tissue volume than those without (37.3 ± 18.9% versus 24.9 ± 12.4%, P = 0.02, and 61.2 ± 18.3 versus 72.6 ± 12.1%, P = 0.04, respectively). Moreover, SF was positively correlated with the percentage of lipid volume on multiple linear regression analysis after adjustment for confounding factors (ß = 0.36, P = 0.03). The interval from stent implantation was similar in both groups (47.0 ± 28.7 versus 37.7 ± 33.3 months; P = 0.39). In conclusion, SF is associated with larger lipid tissue volume within the neointima after DES placement, suggesting a contribution to the development of neoatherosclerosis and vulnerable neointima. Thus SF might lead to future adverse coronary events.

Contractile pericarditis-like hemodynamics in dilated-phase hypertrophic cardiomyopathy with giant atrium.

A 47-year-old man with dilated-phase hypertrophic cardiomyopathy was admitted to the hospital with worsening heart failure. As the enlarged atrium caused a constrictive pericarditis-like hemodynamic condition, atrial wall resection and tricuspid valvuloplasty were performed. Postoperatively, pulmonary artery pressure rose due to increased preload; however, the rise in pulmonary artery wedge pressure was restrained, and the cardiac output significantly improved. When the pericardium is extremely stretched due to atrial enlargement, it can lead to an elevation of intrapericardial pressure, and both atrial volume reduction and tricuspid valve plasty could lead to increased compliance and contribute to hemodynamic improvement. Learning objective: Atrial wall resection for massive atrial enlargement and tricuspid annuloplasty in patients with diastolic-phase hypertrophic cardiomyopathy effectively relieves unstable hemodynamics.

Cardiac sympathetic activity and relationship to cardiac events and left ventricular reverse remodeling in patients with non-ischemic dilated cardiomyopathy.

BACKGROUND: Delayed heart-to-mediastinum ratio (HMR) has been associated with catecholamine levels and contractile reserve in dilated cardiomyopathy (DCM); however, there is scant evidence regarding the association between cardiac sympathetic activity and left ventricular reverse remodeling (LV-RR). We calculated the 123I-metaiodobenzylguanidine (123I-mIBG) HMR and washout rate (WR) in patients with DCM and investigated their associations with LV-RR. METHODS: From April 2003 to January 2020, in 120 patients with DCM who underwent 123I-mIBG scintigraphy. 66 patients undergoing follow-up echo and taking a beta-blocker from baseline were examined the relationship between 123I-mIBG and LV-RR. After that, this prognostic value for composite cardiac events was evaluated in the entire 120 patients. RESULTS: In LV-RR analysis, patients were 50.4 ± 12.2 years, with a mean left ventricular ejection fraction of 28.6%. Of 66 patients, 28 (42.4%) achieved LV-RR. Multiple logistic regression analysis of LV-RR revealed that not delayed HMR but the WR (cutoff value: 13.5%) was an independent predictor of LV-RR (odds ratio 6.514, p = 0.002). In the analysis for composite cardiac events, even though WR itself does not have the prognostic capacity, Kaplan-Meier survival curves divided by the cutoff value (delayed HMR = 2.0, WR = 13.5) showed that delayed HMR and WR values enabled the stratification of high-risk patients (log-rank p < 0.001). CONCLUSIONS: The 123I-mIBG WR was associated with the prevalence of LV-RR in patients taking 100% of beta-blockers and 98.5% of renin-angiotensin system inhibitors. Reflecting the contractile reserve, the combined assessment of the delayed HMR and WR could be used to further precisely stratify the patients with DCM.

Cardiac Rehabilitation in Severe Heart Failure Patients with Impella 5.0 Support via the Subclavian Artery Approach Prior to Left Ventricular Assist Device Implantation.

Impella 5.0 circulatory support via subclavian artery (SA) access may be a safe approach for patients undergoing cardiac rehabilitation (CR). In this case series, we retrospectively analyzed the demographic characteristics, physical function, and CR data of six patients who underwent Impella 5.0 implantation via the SA prior to left ventricular assist device (LVAD) implantation between October 2013 and June 2021. The median age was 48 years, and one patient was female. Grip strength was maintained or increased in all patients before LVAD implantation (pre-LVAD) compared to after Impella 5.0 implantation. The pre-LVAD knee extension isometric strength (KEIS) was less than 0.46 kgf/kg in two patients and more than 0.46 kgf/kg in three patients (unavailable KEIS data, n = 1). With Impella 5.0 implantation, two patients could ambulate, one could stand, two could sit on the edge of the bed, and one remained in bed. One patient lost consciousness during CR due to decreased Impella flow. There were no other serious adverse events. Impella 5.0 implantation via the SA allows mobilization, including ambulation, prior to LVAD implantation, and CR can be performed relatively safely.

The potential of dynamic 99mTc-sestamibi cadmium zinc telluride-single-photon emission computed tomography camera assessing myocardial flow reserve in patients with heart failure with preserved ejection fraction.

Aims: Coronary microvascular dysfunction (CMD) is related to the pathophysiology, mortality, and morbidity of heart failure with preserved ejection fraction (HFpEF). A novel single-photon emission computed tomography (SPECT) camera with cadmium zinc telluride (CZT) detectors allows for the quantification of absolute myocardial blood flow and myocardial flow reserve (MFR) in patients with coronary artery disease. However, the potential of CZT-SPECT assessing for CMD has never been evaluated in patients with HFpEF. Methods and results: The clinical records of 127 consecutive patients who underwent dynamic CZT-SPECT were retrospectively reviewed. Rest and stress scanning were started simultaneously with 3 and 9 MBq/kg of 99mTc-sestamibi administration, respectively. Dynamic CZT-SPECT imaging data were analysed using a net-retention model with commercially available software. Transthoracic echocardiography was performed in all patients. The MFR value was significantly lower in the HFpEF group (mean ± SEM = 2.00 ± 0.097) than that in the non-HFpEF group (mean ± SEM = 2.74 ± 0.14, P = 0.0004). A receiver operating characteristic analysis indicated that if a cut-off value of 2.525 was applied, MFR could efficiently distinguish HFpEF from non-HFpEF. Heart failure with preserved ejection fraction had a consistently low MFR, regardless of the diastolic dysfunction score. Heart failure with preserved ejection fraction patients with MFR values lower than 2.075 had a significantly higher incidence of heart failure exacerbation. Conclusion: Myocardial flow reserve assessed by CZT-SPECT was significantly reduced in patients with HFpEF. A lower MFR was associated with a higher hospitalization rate in these patients. Myocardial flow reserve assessed by CZT-SPECT has the potential to predict future adverse events and stratify the severity of disease in patients with HFpEF.

Recurrent fulminant non-rheumatic streptococcal myocarditis proven by endomyocardial biopsy and autopsy.

A 42-year-old man with a history of acute myocarditis after streptococcal pharyngitis developed recurrent fulminant myocarditis. Endomyocardial biopsy revealed myocyte degeneration, interstitial edema, and neutrophil infiltration. The patient's cardiac function deteriorated rapidly, and he died despite mechanical circulatory support. Autopsy revealed neutrophil infiltration, interstitial edema, and micro-abscesses containing masses of streptococci and neutrophilic phagocytosis within the myocardium. The patient did not meet the diagnostic criteria for acute rheumatic fever; thus, he was diagnosed with non-rheumatic streptococcal myocarditis. Non-rheumatic streptococcal myocarditis rarely recurs, but it can be fulminant upon recurrence. Learning objective: We report a rare case of recurrent fulminant non-rheumatic streptococcal myocarditis. Endomyocardial biopsy and autopsy revealed neutrophil infiltration and micro-abscesses containing bacterial masses of streptococci and neutrophilic phagocytosis in the myocardium. The patient did not meet the diagnostic criteria for acute rheumatic fever; thus, he was diagnosed with non-rheumatic streptococcal myocarditis. Non-rheumatic streptococcal myocarditis rarely recurs, but it can be fulminant upon recurrence.