Outcomes for Atrial Fibrillation Patients with Silent Left Atrial Thrombi Detected by Transesophageal Echocardiography

Although we have occasionally experienced silent thrombi in the left atrium (LA), defined as thrombi free from embolic events, by screening transesophageal echocardiography (TEE) for atrial fibrillation (AF), few data are available on predictors and outcomes of silent LA thrombi in patients with AF. We retrospectively reviewed clinical records and identified 83 patients (2.6%) with silent LA thrombi, out of 4,214 TEE procedures in 3,139 patients with AF at 6 hospitals from January 2010 to December 2012. The median [interquartile range] CHA₂DS₂-VASc score was 3 [2, 5]. Most patients (n = 71, 86%) were taking oral anticoagulants before the TEE, and 59 patients (71%) had heart failure (HF). During follow-up periods of 905 [620, 1301] days, ischemic stroke and systemic embolism, and hemorrhagic stroke occurred only in 3 (3.6%) and 2 patients (2.4%), respectively. All-cause death developed in 14 patients (17%), and cardiac death was the primary cause of death (n = 9, 11%). Multivariate Cox regression analysis showed the composite end point of death, stroke, systemic embolism, and major bleeding was significantly associated with age (hazard ratio; 1.06, 95% confidence interval; 1.01 to 1.11, p = 0.019) and HF (3.18, 1.27 to 7.99, p = 0.014). In conclusion, the incidence of ischemic stroke after detecting silent LA thrombi was relatively low in patients with AF under oral anticoagulation. Advanced age and HF were predictors for worse outcomes in AF patients with silent LA thrombi.

Impact of Angioscopic Evaluation for Femoropopliteal In-Stent Restenosis Before and After Excimer Laser Atherectomy

In-stent restenosis (ISR) is a prevalent problem following stenting of femoropopliteal lesions. A potential novel treatment modality for ISR including excimer laser atherectomy (ELA) has become available. We performed ELA for in-stent chronic total occlusion (CTO) of femoropopliteal lesions and evaluated lesion morphology before and after ELA by angioscopy in 2 patients. The angioscopic findings clearly showed removal of in-stent thrombi after ELA. Thus, ELA may be effective for in-stent CTO of femoropopliteal lesions. This is the first report describing the direct visualization of ELA effect for vaporization of thrombi in femoropopliteal in-stent lesions by angioscopy.

Different risk factors for bleeding and discontinuation between dabigatran and rivaroxaban

BACKGROUND

It is unclear whether risk factors for bleeding and discontinuation are different between dabigatran and rivaroxaban.

METHODS AND RESULTS

We enrolled consecutive patients with atrial fibrillation who received dabigatran or rivaroxaban, had a CHADS2 score >1 and creatinine clearance >30ml/min. During this period, only dabigatran and rivaroxaban were available as non-vitamin K oral anticoagulants (NOACs) in our hospital. We compared the clinical and demographic data and the incidence of bleeding for one year between dabigatran group and rivaroxaban group. As a result, the dabigatran group consisted of 177 patients and the rivaroxaban group consisted of 179 patients. The incidence of discontinuation was significantly higher in the dabigatran group than in the rivaroxaban group (27.7% vs. 13.4%, p<0.001). Multivariate analysis, even after propensity score-matching analysis, revealed that there were no independent risk factors for bleeding in the dabigatran group, while in the rivaroxaban group, use of antiplatelet therapy was an independent factor correlating with bleeding.

CONCLUSIONS

The risk factors for bleeding may be different between dabigatran and rivaroxaban. To avoid bleeding, rivaroxaban should be prescribed with caution or avoided in patients using antiplatelet therapy. Upon discontinuation, rivaroxaban may be more favorable than dabigatran.

A Case of Sudden Cardiac Death due to Pilsicainide-Induced Torsades de Pointes

An 84-year-old male received oral pilsicainide, a pure sodium channel blocker with slow recovery kinetics, to convert his paroxysmal atrial fibrillation to a sinus rhythm; the patient developed sudden cardiac death two days later. The Holter electrocardiogram, which was worn by chance, revealed torsade de pointes with gradually prolonged QT intervals. This drug is rapidly absorbed from the gastrointestinal tract, and most of it is excreted from the kidney. Although the patient's renal function was not highly impaired and the dose of pilsicainide was low, the plasma concentration of pilsicainide may have been high, which can produce torsades de pointes in the octogenarian. Although the oral administration of class IC drugs, including pilsicainide, is effective to terminate atrial fibrillation, careful consideration must be taken before giving these drugs to octogenarians.

Difference of neointimal growth patterns in bifurcation lesions among four kinds of drug-eluting stents: an optical coherence tomographic study

AIM

Neointimal proliferation of bifurcation lesions after implantation of drug-eluting stents (DES) has not been well evaluated. Thus, we compared neointimal proliferation of bifurcation lesions among four DES using optical coherence tomography (OCT).

METHODS

8-month follow-up OCT was performed in 68 bifurcation lesions treated by 15 sirolimus-eluting stents (SES) and 17 paclitaxel-eluting stents (PES) as first-generation DES, and by 17 zotarolimus-eluting stents (ZES) and 19 everolimus-eluting stents (EES) as second-generation DES. Cross-sectional images of the bifurcation lesion using OCT were analyzed every 450 µm. All images were divided into three areas: inner wall of the bifurcation (IB), outer wall of the bifurcation (OB), and ostium of the side branch (SB). We compared the incidence of uncovered struts (IUS) among three areas and the averaged neointimal thickness (NIH) between IB and OB in each stent and also compared these OCT parameters among all DES.

RESULTS

There were no significant differences of IUS between IB and OB in second-generation DES, while in first-generation DES, IUS of IB and OB showed significant differences. The IUS of SES in both areas was significantly higher than in the other DES (all P < 0.001). PES had a significantly higher IUS in SB than the others (all P < 0.001). NIH of OB was significantly higher than that of IB in PES, ZES, and EES, but in SES the NIH was similar in the two areas.

CONCLUSIONS

OCT revealed different neointimal growth patterns among SES, PES, ZES, and EES in bifurcation lesions.

Thin-strut drug-eluting stents are more favorable for severe calcified lesions after rotational atherectomy than thick-strut drug-eluting stents

AIM

Percutaneous coronary intervention (PCI) for severe calcified lesions is still challenging, and there are few studies of drug-eluting stent (DES) implantation for severe calcified lesions, especially regarding long-term results and hemodialysis patients. The study purpose was to clarify the factors, including DES strut thickness, that affect the long-term outcome of severe calcified lesion treated with rotational atherectomy.

METHODS

We analyzed 79 consecutive patients (138 stents) with DES implantation for severe calcified lesions that required rotational atherectomy before stent implantation. Rotational atherectomy was performed for the lesions that showed over 270° severe calcification by intravascular ultrasound (IVUS) or where IVUS could not cross the lesion. We compared coronary risk factors, acute coronary syndrome and hemodialysis, the patients' history of coronary bypass graft and myocardial infarction, medication, and procedure characteristics, including the thickness of the DES used (thin- or thick-strut [>100 μm] DES) between the patients with target vessel revascularization (TVR) versus those without TVR.

RESULTS

During the follow-up, TVR was performed in 30 patients (38.5%). A multivariate analysis revealed that age and thin-strut DES were independently related to TVR (P=.01 for both). A Kaplan-Meier curve showed a lower TVR rate in the thin-strut DES patients compared to the thick-strut DES patients.

CONCLUSIONS

For severe calcified lesions that needed rotational atherectomy, thin-strut DESs resulted in lower rates of TVR compared to thick-strut DESs.

New approach for rotational dyssynchrony using three-dimensional speckle tracking echocardiography

Left ventricular (LV) twist can be evaluated using two-dimensional speckle tracking echocardiography (2DSTE) by analyzing difference between apical and basal rotation. However, it is unable to evaluate global rotational dyssynchrony because it cannot assess mid-wall rotation. Recently developed three-dimensional STE (3DSTE) can investigate LV global rotational dyssynchrony. In this study, we investigated the role of torsion on the long-term effects of cardiac resynchronization therapy (CRT) using 3DSTE. We evaluated 43 patients by 3DSTE: 12 CRT responders, 14 CRT nonresponders, and 17 healthy normal controls. Regional torsion and rotation were assessed using 3DSTE across 16 segments during CRT-off (native conduction) and CRT-on. The following parameters were calculated: global peak twist, Δ global peak twist (difference between CRT-on and CRT-off), and torsion delay index. The torsion delay index was considered to be the rotational energy lost by rotational dyssynchrony. Global peak twist did not show significant differences between the responders and nonresponders during CRT-off (4.0 ± 3.4° vs. 2.8 ± 2.3°, P = 0.295), but it significantly improved in responders compared to nonresponders after CRT-on (5.4 ± 3.5° vs. 2.6 ± 2.6°, P = 0.029). The torsion delay index during CRT-off was significantly higher in responders compared to nonresponders and normal controls (18.5 ± 11.3 vs. 8.6 ± 3.8 and 7.8 ± 5.5, P = 0.010 and P = 0.004, respectively). The torsion delay index during CRT-off significantly correlated with the Δ global peak twist (r = 0.503, P = 0.009). Improvement in LV global peak twist, which is one of the mechanisms for the long-term effects of CRT correlated with the torsion delay index during native conduction that can only be calculated by 3DSTE.

Higher serum uric acid and lipoprotein(a) are correlated with coronary spasm

It has been reported that a major cause of coronary vasospastic angina (VSA) is endothelial dysfunction of the coronary artery. On the other hand, some studies showed that serum uric acid and lipoprotein(a) are correlated with endothelial dysfunction. Thus, we examined whether uric acid and lipoprotein(a), are correlated with VSA. Four hundred forty-one patients with suspected VSA who underwent a coronary angiogram with acetylcholine provocation (ACh test) during an 8-year period were enrolled. We divided them into a VSA group, who showed coronary spasm by the ACh test, and an atypical chest pain (ACP) group, who showed negative ACh test. We compared serum markers between the two groups, including low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, high-sensitivity C-reactive protein (hs-CRP), lipoprotein(a), fibrinogen, total plasminogen activator inhibitor-1, and uric acid. Uric acid, hs-CRP, and lipoprotein(a) were significantly higher in the VSA group than in the ACP group (all P < 0.05) while there were no significant differences in the other parameters. Multivariate analyses identified uric acid and lipoprotein(a) as significant independent markers for VSA. Uric acid and lipoprotein(a) are correlated with VSA, and medical intervention to decrease uric acid and lipoprotein(a) might be effective in controlling VSA.

Valsalva aneurysm filled with thrombi mimicking a cardiac tumor

A Valsalva aneurysm filled with thrombi can be difficult to diagnose, because it mimics a cardiac tumor. Both cardiac magnetic resonance imaging (MRI) and transesophageal echocardiogram (TEE) were performed on a patient who showed a low-echoic mass located between the atrial septum and the non-coronary sinus. Based on MRI findings allowing tissue characterization and the accurate location of the mass and the TEE findings of an irregular surface of the mass and a partial defect in the edge of the non-coronary sinus, we diagnosed the mass as a thrombosed Valsalva aneurysm that had perforated the inter-atrial septum. The operative findings coincided with the preoperative diagnosis. Both MRI and TEE are useful for diagnosing this condition.

Differences in optical coherence tomographic findings and clinical outcomes between excimer laser and cutting balloon angioplasty for focal in-stent restenosis lesions

AIM

In-stent restenosis (ISR), especially focal ISR, after percutaneous coronary intervention (PCI) remains one of the major clinical problems in the drug-eluting stent (DES) era. Several reports have revealed that excimer laser coronary angioplasty (ELCA) is useful for ISR; however, detailed findings after ELCA are unknown. Therefore, we investigated the condition of the neointima after ELCA for ISR with optical coherence tomography (OCT) and compared the OCT findings and clinical outcome between ELCA and cutting-balloon angioplasty (CBA).

METHODS

Twenty-one consecutive patients with focal ISR who underwent ELCA or CBA were enrolled. All patients underwent 12- to 15-month follow-up coronary angiography. OCT was performed immediately after successful PCI to evaluate the neointimal condition in the ISR lesion. We compared the following OCT parameters between ELCA and CBA groups: maximal thickness of remaining in-stent neointima (MTN), number of tears, minimum lumen dimension (MLD), and minimum lumen area (MLA). We also evaluated clinical outcomes, including target vessel revascularization, acute myocardial infarction, death, and stent thrombosis.

RESULTS

MLA in the ELCA group (n = 10) was significantly larger than in the CBA group, and number of tears in the ELCA group was significantly lower than in the CBA group. A trend was shown toward lower TLR with ELCA versus CBA (10.0% vs 45.5%).

CONCLUSIONS

OCT immediately after ELCA for ISR lesions revealed larger lumen area and smaller number of tears compared with CBA, which may support favorable effects of ELCA for focal ISR.

Long-term follow-up of a rare calcified cardiac tumor: a case report

We describe a case of cardiac masses (high- and iso-echoic mass) which were detected by echocardiography in a 57-year-old man with cerebral infarction. Because he refused both biopsy and surgery, the patient was treated with an anticoagulant and antibiotic in our outpatient clinic. During 3-year follow-up, the iso-echoic mass disappeared and the high-echoic mass did not change. Thus, we considered the iso-echoic mass a thrombus and the high-echoic mass a benign tumor. Cardiac computed tomography revealed that the high-echoic mass had extensive calcifications like phleboliths, and magnetic resonance imaging pattern coincided with that of hemangiomas. We conclude that the benign tumor/high-echoic mass might be a vascular malformation.