Role of cardiac CT in the diagnostic evaluation and risk stratification of patients with myocardial infarction and non-obstructive coronary arteries (MINOCA): rationale and design of the MINOCA-GR study

INTRODUCTION

Myocardial infarction with non-obstructive coronary arteries (MINOCA) occurs in 5%-15% of all patients with acute myocardial infarction. Cardiac MR (CMR) and optical coherence tomography have been used to identify the underlying pathophysiological mechanism in MINOCA. The role of cardiac CT angiography (CCTA) in patients with MINOCA, however, has not been well studied so far. CCTA can be used to assess atherosclerotic plaque volume, vulnerable plaque characteristics as well as pericoronary fat tissue attenuation, which has not been yet studied in MINOCA.

METHODS AND ANALYSIS

MINOCA-GR is a prospective, multicentre, observational cohort study based on a national registry that will use CCTA in combination with CMR and invasive coronary angiography (ICA) to evaluate the extent and characteristics of coronary atherosclerosis and its correlation with pericoronary fat attenuation in patients with MINOCA. A total of 60 consecutive adult patients across 4 participating study sites are expected to be enrolled. Following ICA and CMR, patients will undergo CCTA during index hospitalisation. The primary endpoints are quantification of extent and severity of coronary atherosclerosis, description of high-risk plaque features and attenuation profiling of pericoronary fat tissue around all three major epicardial coronary arteries in relation to CMR. Follow-up CCTA for the evaluation of changes in pericoronary fat attenuation will also be performed. MINOCA-GR aims to be the first study to explore the role of CCTA in combination with CMR and ICA in the underlying pathophysiological mechanisms and assisting in diagnostic evaluation and prognosis of patients with MINOCA.

ETHICS AND DISSEMINATION

The study protocol has been approved by the institutional review board/independent ethics committee at each site prior to study commencement. All patients will provide written informed consent. Results will be disseminated at national meetings and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT4186676.

The Interplay between Myocardial Fibrosis, Strain Imaging and Collagen Biomarkers in Adults with Repaired Tetralogy of Fallot

Background: We sought to assess the interplay between right ventricle (RV) fibrosis, biventricular dysfunction based on global longitudinal strain (GLS) analysis, and biomarkers such as Galectin-3 (Gal-3), procollagen type III (PCIII), and NTproBNP. Methods: We studied 35 adult patients with rToF. All patients underwent a cardiac magnetic resonance (CMR) scan including feature tracking for deformation imaging. Blood biomarkers were measured. Results: LGE RV was detected in all patients, mainly at surgical sites. Patients with the highest RV LGE scoring had greater RV dilatation and dysfunction whereas left ventricular (LV) function was preserved. LV GLS correlated with RV total fibrosis score (p = 0.007). A LV GLS value of −15.9% predicted LGE RV score > 8 (AUC 0.754 (p = 0.02)). Neither RV GLS nor biomarker levels were correlated with the extent of RV fibrosis. A cut-off value for NTproBNP of 145.25 pg/mL predicted LGE RV score > 8 points (AUC 0.729, (p = 0.03)). A cut-off value for Gal-3 of 7.42 ng/mL predicted PR Fraction > 20% [AUC 0.704, (p = 0.05)]. Conclusions: A significant extent of RV fibrosis was mainly detected at surgical sites of RV, affecting RV performance. CMR-FT reveals subtle LV dysfunction in rToF patients, due to decreased performance of the fibrotic RV. Impaired LV function and elevated NTproBNP in rToF reflect a dysfunctional fibrotic RV.

How Should I Get Prepared for and Treat Rota Burr Entrapment in a Focally Underexpanded and Restenosed Stent: A Case Report

Although high-speed rotational atherectomy has been successfully used in selected cases of stent underexpansion secondary to heavy peri-stent calcification, a higher risk of burr entrapment demands extreme caution and surgical back-up on site. The main cause of this complication is the lack of diamond dust on the back end of the burr, which prevents backward ablation of tissues when retracted. To date, only few reports of successful burr retrieval using percutaneous bailout techniques have been published. We report a case of burr entrapment within a previously implanted left circumflex artery stent which was successfully recaptured using the dual catheter technique; following the retrieval the patient underwent routine percutaneous coronary intervention.

Micro-CT-Based Quantification of Extracted Thrombus Burden Characteristics and Association With Angiographic Outcomes in Patients With ST-Elevation Myocardial Infarction: The QUEST-STEMI Study

Background: Angiographic detection of thrombus in STEMI is associated with adverse outcomes. However, routine thrombus aspiration failed to demonstrate the anticipated benefit. Hence, management of high coronary thrombus burden remains challenging. We sought to assess for the first time extracted thrombotic material characteristics utilizing micro-computed tomography (micro-CT). Methods: One hundred thirteen STEMI patients undergoing thrombus aspiration were enrolled. Micro-CT was undertaken to quantify retrieved thrombus volume, surface, and density. Correlation of these indices with angiographic and electrocardiographic outcomes was performed. Results: Mean aspirated thrombus volume, surface, and density (±standard deviation) were 15.71 ± 20.10 mm³, 302.89 ± 692.54 mm², and 3139.04 ± 901.88 Hounsfield units, respectively. Aspirated volume and surface were significantly higher (p < 0.001) in patients with higher angiographic thrombus burden. After multivariable analysis, independent predictors for thrombus volume were reference vessel diameter (RVD) (p = 0.011), right coronary artery (RCA) (p = 0.039), and smoking (p = 0.027), whereas RVD (p = 0.018) and RCA (p = 0.019) were predictive for thrombus surface. Thrombus volume and surface were independently associated with distal embolization (p = 0.007 and p = 0.028, respectively), no-reflow phenomenon (p = 0.002 and p = 0.006, respectively), and angiographically evident residual thrombus (p = 0.007 and p = 0.002, respectively). Higher thrombus density was correlated with worse pre-procedural TIMI flow (p < 0.001). Patients with higher aspirated volume and surface developed less ST resolution (p = 0.042 and p = 0.023, respectively). Conclusions: Angiographic outcomes linked with worse prognosis were more frequent among patients with larger extracted thrombus. Despite retrieving larger thrombus load in these patients, current thrombectomy devices fail to deal with thrombotic material adequately. Further studies of novel thrombus aspiration technologies are warranted to improve patient outcomes. Clinical Trial Registration: QUEST-STEMI trial ClinicalTrials.gov number: NCT03429608 Date of registration: February 12, 2018. The study was prospectively registered.

Torsades de Pointes and Prolonged Self-Terminating Ventricular Fibrillation Induced by Amiodarone

A 71-year-old man with a recent diagnosis of pneumonia developed paroxysmal atrial fibrillation and was admitted to the cardiology service. Amiodarone was administered intravenously to restore sinus rhythm. Significant prolongation of the QT interval (QTc = 640ms) was noted and an exceedingly prolonged (over 3 minutes), self-terminating, episode of ventricular flutter/fibrillation occurred during bedside monitoring. The event was terminated without first converting to a more organized ventricular rhythm and without any adverse neurological sequelae. Apart from the long duration of ventricular fibrillation and its spontaneous termination, our case highlights the importance of the continuous heart rhythm monitoring in patients with extreme QT interval prolongation.

Calcification of coronary arteries and aortic valve and circulating a-klotho levels in patients with chronic kidney disease

Background

Evidence suggests that the anti-aging protein a-Klotho is a central modulator of mineral homeostasis. Circulating a-Klotho exerts endocrine activity and has been implicated in the process of vascular calcification, which is accelerated in patients with chronic kidney disease (CKD) and portends an unfavorable overall prognosis. However, the role of a-Klotho in this process remains unclear. The purpose of this study was to investigate the possible interaction between a-Klotho and the calcification of the aortic valve and coronary arteries in patients with CKD.

Methods

In this study we enrolled a total of 60 adult patients with CKD. Group 1 included 30 participants with CKD stage V and group 2 included 30 participants with CKD stage III.

Results

Participants in group 1 had lower levels of circulating a-Klotho compared to group 2 (390; 280–590 vs. 722; 501–897 pg/mL; P=0.001), were of younger age (55.5; 45–63 vs. 69; 62–74 years; P<0.001), had lower body mass index (25.6; 23.8–27.5 vs. 28.2; 25.7–31.1 kg/m²; P=0.036), higher serum phosphate (4.75; 4–5.6 vs. 3.35; 2.9–3.8 mg/dL; P<0.001), higher calcium-phosphate product (41; 35.1–49.2 vs. 31.5; 28.6–35 mg²/dL²; P<0.001), and higher parathyroid hormone (PTH) levels (28.4; 15–44.6 vs. 7.05; 4.3–10.2 pmol /L; P<0.001).

Conclusions

No statistically significant difference was found between the two groups in terms of coronary arteries and aortic valve calcification. Calcitonin, PTH and phosphate were identified as predictors for circulating a-Klotho levels whereas, only hyperlipidemia was identified as predictor for coronary artery calcification. In conclusion, circulating a-Klotho is found to decrease with worsening CKD severity but no correlation was found between the levels of a-Klotho and severity of coronary arteries and aortic valve calcification.

Massive coronary artery air embolism due to an unusual cause

A 46-year-old man underwent angioplasty of a restenotic bifurcation lesion of the circumflex artery. The procedure required repeated balloon exchanges and during the last balloon inflation, no balloon was visualized. A test injection revealed a massive coronary air embolism due to expulsion of air that had accumulated in the guiding catheter shaft. The patient was rapidly resuscitated from electromechanical dissociation with intracoronary injection of adrenaline and atropine and forceful intracoronary saline injections. Inspection of the balloon revealed a defect and scratch marks at the junction of the wire part and shaft of the monorail balloon, a location that places the air leakage inside the guiding catheter. This is the first report of massive intracoronary air embolism due to an undetectable damage to the shaft of a balloon angioplasty catheter. Recognition of the problem and immediate intervention is vital in limiting the duration of cardiac dysfunction.

A case of sarcoidosis-associated pulmonary hypertension masquerading as chronic thromboembolic pulmonary hypertension

Occlusive vasculopathy due to the development and accumulation of granulomas at the level of intima of large vessels, as well as mediastinal lymph nodes and fibrosing mediastinitis secondary to sarcoidosis, causing extrinsic compression of mediastinal vascular structure are uncommon mechanisms of sarcoidosis-associated pulmonary hypertension. We present a case of a 62-year-old woman with a rare manifestation of sarcoidosis, which was misclassified and treated as chronic thromboembolic pulmonary hypertension for a long period. Fluorine-18-fluorodeoxyglucose positron emission tomography played a major role in accessing final diagnosis. Mechanisms that lead to development of pulmonary hypertension, the contribution of novel imaging modalities, and treatment options are discussed.

Data on diagnostic performance of stress perfusion cardiac magnetic resonance for coronary artery disease detection at the vessel level

Stress perfusion cardiac magnetic resonance (CMR) has been proposed as an important gatekeeper for invasive coronary angiography (ICA) and percutaneous coronary interventions (PCI) in patients evaluated for possible coronary artery disease (CAD) (Fihn et al., 2012; Montalescot et al., 2013) [1], [2]. Several meta-analyses have evaluated the accuracy of stress perfusion CMR to diagnose CAD at the vessel level (Danad et al., 2017; Dai et al., 2016; Jiang et al., 2016; Takx et al., 2015; Li et al., 2015; Desai and Jha, 2013; Jaarsma et al. 2012; Hamon et al., 2010; Nandalur et al. 2007) [3], [4], [5], [6], [7], [8], [9], [10], [11]. However, they included in the same analysis studies with different definitions of significant CAD (i.e. fractional flow reserve [FFR] < 0.75 and < 0.80 or coronary stenosis ≥ 50% and ≥ 70%), magnetic field strength (1.5 or 3 Tesla [T]), and study protocol (integration or not of late gadolinium enhancement [LGE] into stress perfusion protocol). Data of 34 studies (6091 arteries) have been pooled with the aim of analyzing the accuracy of stress perfusion CMR for the diagnosis of ischemic heart disease at the vessel level according to different definitions of significant CAD, magnetic field strength and study protocol (Arnold et al., 2010; Bettencourt et al., 2013; Cheng et al., 2007; Chiribiri et al., 2013; Cury et al., 2006; De Mello et al., 2012; Donati et al., 2010; Ebersberger et al., 2013; Gebker et al., 2008; Greulich et al., 2015; Hussain et al., 2016; Ishida et al., 2005, 2003; Kamiya et al., 2014; Kitagawa et al., 2008; Klein et al., 2008; Klem et al., 2006; Klumpp et al., 2010; Krittayaphong et al., 2009; Lockie et al., 2011; Ma et al., 2012; Merkle et al., 2007; Meyer et al., 2008; Mor-Avi et al., 2008; Pan et al., 2015; Papanastasiou et al., 2016; Pons Lladó et al., 2004; Sakuma et al., 2005; Salerno et al., 2014; Scheffel et al., 2010; van Werkhoven et al., 2010; Walcher et al., 2013; Watkins et al., 2009; Yun et al., 2015) [12–45]. This article describes data related article titled “Diagnostic Performance of Stress Perfusion Cardiac Magnetic Resonance for the Detection of Coronary Artery Disease” (Kiaos et al., submitted for publication) [46].

Diagnostic performance of stress perfusion cardiac magnetic resonance for the detection of coronary artery disease: A systematic review and meta-analysis

INTRODUCTION

The purpose of this study was to investigate the accuracy of qualitative stress perfusion cardiac magnetic resonance (CMR) to diagnose ischemia-causing lesions according to different definitions of significant coronary artery disease (CAD), and magnetic field strength.

METHODS

We searched PubMed, Web of Science, and the Cochrane Library for studies evaluating diagnostic performance of qualitative stress perfusion CMR for diagnosis of CAD versus coronary angiography or fractional flow reserve (FFR) from inception to 10 September 2017. We used hierarchical models to synthesize the available data.

RESULTS

Sixty-seven studies (7113 patients) met the inclusion criteria. The patient-based analysis of studies using FFR as the reference standard demonstrated a mean sensitivity of 0.90 (95% confidence interval [CI], 0.85-0.93) and a mean specificity of 0.85 (95% CI, 0.80-0.89). The patient-based analyses for detecting coronary stenosis ≥50% and coronary stenosis ≥70% at 1.5T and for detecting coronary stenosis ≥50% and coronary stenosis ≥70%, at 3T, demonstrated a mean sensitivity of 0.82 (95% CI, 0.79-0.84), 0.86 (95% CI, 0.83-0.89), 0.90 (95% CI, 0.82-0.95), and 0.91 (95% CI, 0.79-0.96), respectively; with a mean specificity of 0.75 (95% CI, 0.71-0.80), 0.77 (95% CI, 0.71-0.81), 0.79 (95% CI, 0.69-0.86), and 0.74 (95% CI, 0.59-0.85).

CONCLUSION

Qualitative stress perfusion CMR has high accuracy for the diagnosis of CAD, irrespective of the reference standard and the magnet strength. Studies using FFR as the reference standard had higher diagnostic accuracy on a patient level compared to studies using coronary angiography, with a notable difference in specificity.

Pregnancy outcome in women with congenital heart disease: A single-center experience

OBJECTIVE

Pregnancies in patients with adult congenital heart disease (ACHD) are often complicated. We aimed to highlight the nature and the rate of these complications in a single-center patient population.

METHODS

We retrospectively studied all the pregnancies of women who presented on an outpatient basis, and all pregnancies were reviewed for maternal and fetal outcomes.

RESULTS

Of 117 pregnancies from 52 ACHD patients (age at pregnancy 28.3 ± 6.6 years), 10 were therapeutically aborted. A proportion of 41.1% of the remaining 107 pregnancies were complicated either with cardiac (3.7%), obstetric (15.0%), or fetal/neonatal (11.2%) adverse events or with spontaneous abortion (17.8%). Hospitalization during pregnancy was required in 10 patients. Elective cesarean sections were initially planned for 31% of the 87 pregnancies, which were finally completed, while 8% required an emergency cesarean section, mostly for obstetric reasons. NYHA class deterioration after pregnancy was detected in 9.3% of our cohort. Modified WHO class III/IV, prior medication use, and higher body mass index (BMI) were related to cardiac complications during pregnancy or NYHA deterioration.

CONCLUSION

Pregnancies in ACHD patients are at high risk for complications. Advanced modified WHO class, prior medication use, and high BMI were related to adverse cardiac events.

Iatrogenic Lutembacher Syndrome after Percutaneous Mitral Commissurotomy

Atrial septal defects (ASDs) are common immediately after percutaneous mitral commissurotomy (PMC). They are usually small, hemodynamically insignificant, and tend to decrease or disappear within 6 to 12 months. Herein, a case is described of persistent ASD in a patient with mitral valve stenosis who had undergone successful PMC three years previously. The patient had signs and symptoms of right heart failure and severe tricuspid regurgitation (TR) with borderline right ventricular systolic function on echocardiography, in addition to the ASD. Cardiac magnetic resonance (CMR) imaging played a significant role in decision-making by clarifying the anatomy of the ASD and severity of the shunt, measuring right ventricular systolic function, and providing absolute quantification for TR. The right ventricular systolic function was normal on CMR, rendering the patient suitable for surgical treatment. Persistent iatrogenic ASDs have become an increasingly common finding after invasive procedures requiring trans-septal puncture and the manipulation of catheters. Multimodality imaging can provide significant aid in the management of patients with valvular heart disease complicated by iatrogenic shunts.

Atrial septostomy and disease targeting therapy in pulmonary hypertension secondary to neurofibromatosis

BACKGROUND

Neurofibromatosis type 1 (NF1) is a rare multisystem genetic disorder. During the course of the disease it can be rarely complicated with pulmonary hypertension (PH) which confers a dismal prognosis.

CASE PRESENTATION

We describe the case of a 57-year-old female patient with NF1 complicated by severe precapillary PH despite dual disease-specific oral combination therapy. The patient was treated with initial atrial septostomy followed by administration of high-dose subcutaneous treprostinil with a favorable medium-term clinical and hemodynamic response.

CONCLUSIONS

PH secondary to NF1 may be successfully treated with the combination of atrial septostomy and PH targeted therapy in selected patients.

Initial Experience with Renal Denervation for the Treatment of Resistant Hypertension - The Utility of Novel Anesthetics and Metaiodobenzylguanidine Scintigraphy (MIBG)

Background:

The Symplicity-HTN 3 trial failed to show significant difference in blood pressure (BP) lowering between patients undergoing catheter-based renal denervation (RDN) and the sham-procedure arm of the study. However, there is still optimism about the role of RDN in the treatment of resistant hypertension, because identification of patients with increased sympathetic activity thus being good RDN responders, improvements in the RDN procedure and new technology RDN catheters are all expected to lead to better RDN results. We present our initial experience with RDN for the treatment of resistant hypertension, and the utility of novel anesthetics and cardiac ¹²³I-metaiodobenzylguanidine scintigraphy (¹²³I-MIBG).

Methods and Results:

Seven patients with resistant hypertension underwent RDN and were followed up for 6 months. MIBG was performed before RDN, in order to estimate sympathetic activity and predict the response to RDN. All patients were sedated with dexmedetomidine and remifentanil during RDN. All patients tolerated the procedure well, were hemodynamically stable and their peri-procedural pain was effectively controlled. A median of 7.6 ± 2.1 and 6 ± 1.4 ablations were delivered in the right and left renal artery respectively, making an average of 6.8 burns per artery. No peri-procedural or late complications - adverse events (local or systematic) occurred. At 6 months, mean reduction in office BP was -26.0/-16.3 mmHg (p=0.004/p=0.02), while mean reduction in ambulatory BP was -12.3/-9.2 mmHg (p=0.118/p=0.045). One patient (14.3%) was a non-responder. None of the cardiac ¹²³I-MIBG imaging indexes(early and late heart-to-mediastinum (H/M) count density ratio, washout rate (WR) of the tracer from the myocardium) were different between responders and non-responders.

Conclusion:

Patients with resistant hypertension who underwent RDN in our department had a significant reduction in BP 6 months after the intervention. ¹²³I-MIBG was not useful in predicting RDN response. Dexmedetomidine and remifentanil provided sufficient patient comfort during the procedure, allowing an adequate number of ablations per renal artery to be performed, and this could probably lead to improved RDN results.

Embolization after percutaneous coronary intervention in acute coronary syndrome. Saphenous vein grafts versus native coronary arteries

AIMS

The aim of this study was to assess the occurrence of distal embolization and to quantify the amount of embolic material captured during stent implantation in native coronary arteries, as compared with saphenous vein grafts (SVG) in patients at different time periods after an acute coronary syndrome.

PATIENTS AND METHODS

In all, 104 patients presenting with unstable or stable angina underwent percutaneous coronary intervention (PCI) in 107 vessels and stent implantation in 112 lesions, 53 % of which were in SVG.

RESULTS

Device deployment and retrieval was successful in 111 lesions. Embolic material was detected in 74 % of the protection devices. Early PCI, during a 2-week period after the last ischemic episode, was associated with larger embolic load, especially in the right coronary artery. The length of the lesion was the only preprocedural independent variable that was found to be a significant predictor for the presence of emboli (p = 0.002). The stent diameter and the maximum dilatation pressure were the two procedural variables found to be significant predictors for the presence of emboli (p = 0.025 and p = 0.008, respectively). The irregularity of the lesion and the number of stents deployed were found to have a predictive correlation to the total area of the embolic particles (p = 0.04 and p = 0.005, respectively).

CONCLUSION

Distal embolization of atherosclerotic debris is a frequent phenomenon after PCI not only in SVG but also in native vessels. The amount of embolic material seems to be related to the atherosclerotic burden of the vessel and to the early timing of the procedure as related to acute coronary syndrome.

Paravalvular aortic prosthetic valve leak closure: technical aspects of the percutaneous approach

We describe the successful closure of an aortic paravalvular bioprosthetic valve leak with the simultaneous percutaneous deployment of two vascular plugs.

Surgical septal myectomy for hypertrophic cardiomyopathy in Greece: a single-center initial experience

INTRODUCTION

Surgical septal myectomy is thought to be the gold standard of treatment for obstructive hypertrophic cardiomyopathy (HCM) with obstruction symptoms refractory to optimal medical therapy. In Europe, during the last 2 decades, myectomy has been set aside, while alcohol septal ablation has been widely promoted. In this paper, we analyze our first experience of surgical septal myectomy in a small cohort of patients with HCM coming from a single tertiary center.

METHODS

Thirty-two patients (16 male, 50%) with a mean age of 58.1 ± 14.4 (range 12-79 years) underwent myectomy for HCM symptoms refractory to negative inotropic agents. The technique used for the myectomy was the one introduced by Andrew Morrow. Mean follow-up time after procedure was 16.8 ± 13.3 months with a median of 13 months (range 4-58 months).

RESULTS

Post-myectomy, there was a significant improvement in patients' NYHA class (from 3.3 ± 0.46 to 1.38 ± 0.49, p<0.0005), while interventricular septum thickness was reduced from 2.3 ± 0.4 cm to 1.6 ± 0.4 cm (p<0.0005), and peak gradient at the site of obstruction from 94.9 ± 29 to 16.7 ± 7.9 mmHg (p<0.0005). During the follow-up period, only 1 out of 32 patients died, from non-cardiovascular causes, with the overall survival post-myectomy being 97.2% (95%CI: 94.5-99.9%) at 1-year follow up.

CONCLUSIONS

Surgical septal myectomy in patients with HCM and drug-refractory symptoms is a safe procedure that greatly improves symptoms and quality of life. Further follow-up of our patients is mandatory in order to determine whether the good survival rate achieved at 1 year will persist.

Quinidine: an "endangered species" drug appropriate for management of electrical storm in brugada syndrome

Brugada syndrome is an inherited channelopathy associated with an increased risk of syncope and sudden cardiac death. In rare cases it can be manifested with electrical storm. We report two cases of Brugada syndrome that presented with electrical storm and were treated successfully with oral quinidine, an "endangered species" drug.

Prevalence of "distressed" personality in patients with coronary artery disease and its correlation with morbidity after coronary surgery

INTRODUCTION

The "distressed" (Type-D) personality is an emerging risk factor in cardiovascular diseases and is associated with an increased risk of impaired quality of life, morbidity and mortality. The purpose of this study was to explore the prevalence of Type-D personality among patients with coronary artery disease (CAD) and its association with the development of complications following coronary artery bypass grafting surgery.

METHODS

A Greek version of the Type-D Personality Scale-14 (DS14), along with the Hospital Anxiety and Depression Scale (HADS) as well as the Ways of Coping Questionnaire (WCQ), were used. A cohort of 323 patients with CAD was examined.

RESULTS

The prevalence of Type-D personality among Greek patients with CAD was found to be 18.24%. Type-D patients showed a higher rate of anxiety and depression compared to non Type-D patients. Type-D was also associated with passive coping and negatively correlated with active coping. Regarding postoperative morbidity, type-D patients were at an increased risk of developing postoperative atrial fibrillation, while no significant differences were found in the development of any other complication.

CONCLUSIONS

The impact of Type-D personality on health outcomes should be studied further, both in clinical samples and in the general population.

Clinical characteristics and natural history of hypertrophic cardiomyopathy with midventricular obstruction

BACKGROUND

The prevalence, clinical characteristics and natural history of patients with hypertrophic cardiomyopathy (HCM) and midventricular obstruction (MVO) have not been adequately studied.

METHODS AND RESULTS

A single-center cohort consisting of 423 patients (mean age, 49.3±17.2 years; 66.2% male) was thoroughly followed up for a median of 84 months (7 years; range, 6-480 months). MVO, characterized by the echocardiographic appearance of midventricular muscular apposition with a simultaneous mid-cavitary gradient ≥30mmHg, was identified in 34 patients (8%). Patients with MVO tended to be more symptomatic during their initial evaluation (>90% presented with NYHA class ≥II) compared to the rest of the HCM cohort. Apical aneurysm formation was identified in more than one-fourth of patients with MVO (26.5%), being a characteristic of the group. On multivariate Cox regression hazard analysis, presence of MVO strongly predicted progression to end-stage (burnt out) HCM and related heart failure (HF) deaths (hazard ratio, [HR], 2.62; 95% confidence interval [CI]: 1.2-8.8; P=0.047), as well as sudden death and associated lethal arrhythmic events (HR, 3.3; 95% CI: 1.26-8.85; P=0.016).

CONCLUSIONS

MVO is a distinct phenotype of HCM associated with unfavorable prognosis in terms of end-stage HCM, sudden death and lethal arrhythmic events. The high adverse outcome rate necessitates early recognition of MVO and appropriate therapeutic interventions.

Successful high-risk percutaneous coronary intervention with the use of minimal extracorporeal circulation system

Minimal extracorporeal circulation (MECC) represents a contemporary system which integrates several advances in cardiopulmonary bypass technology in a single circuit. We challenged the efficacy of the MECC system to support the circulation in elective high-risk percutaneous coronary intervention (PCI). A 78-year-old patient with complex coronary disease who would have been otherwise rejected for interventional therapy underwent PCI with rotablation on MECC support. The MECC system provided hemodynamic support at a flow of 1.8 L min(-1) m(-2) while perfusion pressure was kept at a minimum of 70 mm Hg. This allowed for successful angioplasty of the left main stem and a chronically occluded right coronary artery, which otherwise produced significant hemodynamic compromise. This case illustrates that mechanical circulatory support with the MECC system could provide a stable environment and a "safety net" for carrying out complex percutaneous coronary intervention in high-risk patients.

Spontaneous dissection of right coronary artery manifested with acute myocardial infarction

Spontaneous coronary artery dissection is a rare cause of acute ischemic coronary events and sudden cardiac death. It usually occurs in young women without traditional risk factors for coronary artery disease during pregnancy or postpartum period. However, it has also been reported in patients with atherosclerotic coronary disease. We present a case of spontaneous right coronary artery dissection in a 48-year male with recent myocardial infarction and previous percutaneous coronary intervention.

Segmental diastolic compression of venous and arterial conduits post coronary artery bypass surgery

In a case of constrictive pericarditis post coronary artery bypass surgery we describe the diastolic compression of venous and arterial conduits and the timing of compression, as demonstrated during angiography, before and after pericardiectomy. In conclusion, angiographic demonstration of conduit compression is only suggestive of constriction, and consideration of the timing of compression during diastole should be a more specific sign.

Prevalence and clinical outcomes of incidentally diagnosed hypertrophic cardiomyopathy

The purpose of the present study was to evaluate the prevalence and prognosis of patients incidentally diagnosed with hypertrophic cardiomyopathy (HC). We studied 380 consecutive patients with HC (49.3 +/- 17.2 years; 65% men) for a median of 58 months (range 6 to 454). The patients were divided into 2 groups: those incidentally diagnosed from routine examination findings (precordial murmur and/or abnormal electrocardiographic findings) and those diagnosed either because of symptomatic status or by screening because of a family history of HC. Those patients who had been incidentally diagnosed constituted 29.2% of our study cohort. Although overall mortality did not differ between the 2 groups (p = 0.12), the patients diagnosed either because of symptoms or a family history tended to have at least a 4.5-fold greater risk of cardiovascular death (relative risk 4.5, 95% confidence interval 1.04 to 19.6, p = 0.04) and a 4.22 greater risk of sudden death (relative risk 4.22, 95% confidence interval 1.0 to 18.22, p = 0.04). Despite the greater sudden death mortality among the nonincidentally diagnosed patients, no statistically significant difference was found concerning the sudden death risk factor frequency (p = 0.96) between the 2 groups. In conclusion, the discrepancy between the low numbers of patients reported by published registries and the relatively high prevalence of the disease in the general population can be attributed to the large number of patients who remain asymptomatic, even throughout their life, awaiting an accidental diagnosis. Those patients with an incidental diagnosis have a more benign course, as shown by the total cardiovascular and composite sudden death mortality. A high level of awareness and suspicion for HC among physicians is essential for clinical recognition of such patients.

Management of left ventricular free wall rupture under extracorporeal membrane oxygenation support

This is a case report of a patient with left ventricular free wall rupture after acute myocardial infarction that was managed successfully with the use of an extracorporeal membrane oxygenation circuit for resuscitation, surgical repair and postoperative circulatory support. Conversion to conventional cardiopulmonary bypass for surgical repair was avoided. Decompression of the left ventricle during the postoperative period promotes myocardial recovery and leads to improved fixation of surgical repair.

Spontaneous coronary artery dissection and acute myocardial infarction during pregnancy

Spontaneous coronary artery dissection is a rare cause of infarction in the general population, but a common cause of myocardial infarction during pregnancy, and even nowadays carries a high risk of mortality. We describe the case of a 31-year-old primigravida who presented during the 34th week of pregnancy with the chief complaint of chest pain and was found to suffer from myocardial infarction. She was otherwise healthy and had no known risk factors for coronary artery disease. The patient was treated conservatively with nitrates, aspirin, heparin and beta-blockers, eventually sustained a large myocardial infarction and, after an initial period of instability, remained asymptomatic. A week later she delivered 3 healthy babies. A coronary angiogram performed 3 months after the initial event revealed an extensive obstructive dissection of the circumflex coronary artery. The decision whether to pursue percutaneous coronary intervention, surgical revascularisation or appropriate medical therapy, is based on clinical presentation, the extent of the dissection, and the amount of ischaemic myocardium at risk. Cardiologists must be aware of this rare entity during pregnancy or postpartum, since early diagnosis and treatment are crucial for the survival of the mother and the foetus.

Identification of high risk patients with hypertrophic cardiomyopathy in a northern Greek population

Background

The percentage of hypertrophic cardiomyopathy (HCM) patients who are in high risk for Sudden Death (SD) constitutes only a minority of all HCM population but the incidence of SD in this subset is high (at least 5% annually). The identification of this small but important proportion of high risk HCM patients has been the clue in the clinical evaluation of these patients.

Methods

Our study cohort consisted from 123 patients with HCM who are currently followed up in our Institution. Five clinical risk factors were assessed: a family history of premature SD, unexplained syncope, Non Sustained Ventricular Tachycardia (NSVT) on 24-h ECG monitoring, Abnormal Blood Pressure Response (ABPR) during upright exercise testing and Maximum left ventricular Wall Thickness (MWT) ≥30 mm. The purpose of our study was the identification of high risk HCM patients coming from Northern Greece.

Results

Fifteen patients (12.2%) of the whole cohort had MWT ≥ 30 mm, 30 patients (24.4%) had an ABPR to exercise, 17 patients (13.8%) had episodes of NSVT in 24-h Holter monitoring, 17 patients (13.8%) suffered from syncope, and 8 patients (6.5%) had a positive family history of premature SD. Data analysis revealed that 74 patients (60.1%) had none risk factor. Twenty four patients (19.5%) had 1 risk factor, 17 patients (13.8%) had 2 risk factors, 4 patients (3.25%) had 3 risk factors, and 4 patients (3.25%) had 4 risk factors, while none patient had 5 risk factors. Twenty five patients (20.3%) had 2 or more risk factors.

Conclusion

This study for the first time confirms that, although a 60% of patients with HCM coming from a regional Greek population are in low risk for SD, a substantial proportion (almost 20%) carries a high risk for SD justifying prophylactic therapy with amiodaron or ICD implantation.

Diagnostic value of stored electrograms in pacemaker patients

OBJECTIVE

Stored electrograms (EGMs) are diagnostic tools in modern pacemakers, providing data concerning arrhythmia occurrence and device function. We sought to validate the impact of stored EGMs on diagnosis and verification of arrhythmias presented after pacemaker implantation.

METHODS AND RESULTS

We enrolled 71 consecutive patients (mean age 64 +/- 8 years, 51 men) with a standard indication for pacemaker implantation. The following pacemaker devices were implanted: DDDR = 57, VDDR = 5, VVIR = 9. EGM triggers were atrial tachycardia (AT), non-sustained ventricular tachycardia (NSVT) and ventricular tachycardia (VT). We retrieved and analysed 362 EGMs at 3 and 6 months after implantation. The EGMs were triggered by AT in 260 EGMs (72%), by NSVT in 80 (22%) and by VT in 22 (6%). In total, 243 episodes (67%) confirmed the arrhythmic events, while 119 episodes (33%) were classified as false-positive. They were divided into false-positive AT in 85 EGMs (33%), false-positive NSVT in 28 (35%) and false-positive VT in 6 EGMs (27%). The false-positive AT cases were caused by ventricular far-field sensing from the atrial channel in 34 EGMs (40%) and noise or myopotentials in 51 EGMs (60%). Most of the false-positive VT and NSVT episodes were due to atrial fibrillation or atrial tachycardias in 21 EGMs (62%), while the rest were caused by noise in 11 EGMs (32%) or ventricular T wave oversensing in 2 EGMs (6%).

CONCLUSIONS

Stored EGMs in pacemaker patients were diagnostic in two thirds of arrhythmic episodes. They are useful tools to diagnose arrhythmias and identify sensing problems, and they contribute to optimal device programming and patient management.

Left main coronary artery stenosis after aortic valve replacement

We describe two cases with iatrogenic left main coronary artery stenosis where a symptomatology of unstable angina appeared within three months of aortic valve replacement surgery. One patient was treated with aortocoronary bypass and the other with angioplasty and stenting.

Coronary vessel perforation during balloon angioplasty: a case report

Coronary perforation can be managed with prolonged balloon inflations, covered stents, or embolization of the vessel. We report on a case of a balloon-induced perforation of the distal left anterior descending artery, that was sealed by injecting preclotted autologous blood through the balloon catheter lumen at the site of the perforation. The patency of the distal vessel was maintained.