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Background Clinical studies have reported that epicardial adipose tissue (EpAT) accumulation associates with the progression of atrial fibrillation (AF) pathology and adversely affects AF management. The role of local cardiac EpAT deposition in disease progression is unclear, and the electrophysiological, cellular, and molecular mechanisms involved remain poorly defined. Objectives The purpose of this study was to identify the underlying mechanisms by which EpAT influences the atrial substrate for AF. Methods Patients without AF undergoing coronary artery bypass surgery were recruited. Computed tomography and high-density epicardial electrophysiological mapping of the anterior right atrium were utilized to quantify EpAT volumes and to assess association with the electrophysiological substrate in situ. Excised right atrial appendages were analyzed histologically to characterize EpAT infiltration, fibrosis, and gap junction localization. Co-culture experiments were used to evaluate the paracrine effects of EpAT on cardiomyocyte electrophysiology. Proteomic analyses were applied to identify molecular mediators of cellular electrophysiological disturbance. Results Higher local EpAT volume clinically correlated with slowed conduction, greater electrogram fractionation, increased fibrosis, and lateralization of cardiomyocyte connexin-40. In addition, atrial conduction heterogeneity was increased with more extensive myocardial EpAT infiltration. Cardiomyocyte culture studies using multielectrode arrays showed that cardiac adipose tissue-secreted factors slowed conduction velocity and contained proteins with capacity to disrupt intermyocyte electromechanical integrity. Conclusions These findings indicate that atrial pathophysiology is critically dependent on local EpAT accumulation and infiltration. In addition to myocardial architecture disruption, this effect can be attributed to an EpAT-cardiomyocyte paracrine axis. The focal adhesion group proteins are identified as new disease candidates potentially contributing to arrhythmogenic atrial substrate.

Background Mitral valve procedures remain a surgical challenge in the presence of extensive annular calcification, which presents a formidable technical challenge. Aggressive debridement is limited by risk of serious complications and the technical complexity of pericardial patch reconstruction of the debrided area. Methods An open surgical approach with a transcatheter valve allows the valve to be placed under direct visualisation to facilitate positioning and to evaluate the likelihood of both perivalvular leakage and atrioventricular disruption. The open approach has the additional advantage of performing concomitant surgeries like other valve procedures, arrhythmias surgeries and coronary bypass. Results We present our experience with open surgical mitral valve replacement (MVR) using transcatheter valve in different patients requiring varied procedures. These patients were not suitable for MVR using standard prosthetic valve and techniques. They were also not suitable for percutaneous MVR because of heavily calcified anterior mitral leaflet and the other concomitant procedures required. Conclusions Open MVR with a transcatheter balloon-expandable valve can avoid the need for technically challenging and high-risk decalcification of mitral annulus. These novel techniques using transcatheter valves can be successful in complex cases where standard prosthetic valves are impossible to implant in a heavily calcified mitral annulus.

Background: Endocardial-epicardial dissociation and focal breakthroughs in humans with atrial fibrillation (AF) have been recently demonstrated using activation mapping of short 10-second AF segments. In the current study, we used simultaneous endo-epi phase mapping to characterize endo-epi activation patterns on long segments of human persistent AF. Methods: Simultaneous intraoperative mapping of endo- and epicardial lateral right atrium wall was performed in patients with persistent AF using 2 high-density grid catheters (16 electrodes, 3 mm spacing). Filtered unipolar and bipolar electrograms of continuous 2-minute AF recordings and electrodes locations were exported for phase analyses. We defined endocardial-epicardial dissociation as phase difference of ≥20 ms between paired endo-epi electrodes. Wavefronts were classified as rotations, single wavefronts, focal waves, or disorganized activity as per standard criteria. Endo-Epi wavefront patterns were simultaneously compared on dynamic phase maps. Complex fractionated electrograms were defined as bipolar electrograms with ≥5 directional changes occupying at least 70% of sample duration. Results: Fourteen patients with persistent AF undergoing cardiac surgery were included. Endocardial-epicardial dissociation was seen in 50.3% of phase maps with significant temporal heterogeneity. Disorganized activity (Endo: 41.3% versus Epi: 46.8%, P =0.0194) and single wavefronts (Endo: 31.3% versus Epi: 28.1%, P =0.129) were the dominant patterns. Transient rotations (Endo: 22% versus Epi: 19.2%, P =0.169; mean duration: 590±140 ms) and nonsustained focal waves (Endo: 1.2% versus Epi: 1.6%, P =0.669) were also observed. Apparent transmural migration of rotational activations (n=6) from the epi- to the endocardium was seen in 2 patients. Electrogram fractionation was significantly higher in the epicardium than endocardium (61.2% versus 51.6%, P Conclusions: Simultaneous endo-epi phase mapping of prolonged human persistent AF recordings shows significant Endocardial-epicardial dissociation marked temporal heterogeneity, discordant and transitioning wavefronts patterns and complex fractionations. No sustained focal activity was observed. Such complex 3-dimensional interactions provide insight into why endocardial mapping alone may not fully characterize the AF mechanism and why endocardial ablation may not be sufficient. Graphic Abstract: A graphic abstract is available for this article.

Background The 3-dimensional (3D) nature of sinoatrial node (SAN) function has not been characterized in the intact human heart. Objective The purpose of this study was to characterize the 3D nature of SAN function in patients with structural heart disease (SHD) using simultaneous endocardial–epicardial (endo–epi) phase mapping. Methods Simultaneous intraoperative endo–epi SAN mapping was performed during sinus rhythm at baseline (SRbaseline) and postoverdrive suppression at 600 ms (SRpost-pace600) and 400 ms (SRpost-pace400) using 2 Abbott Advisor HD Grid Mapping Catheters. Unipolar and bipolar electrograms (EGMs) were exported for phase analysis to determine (1) activation exits; (2) wavefront propagation sequence; (3) endo–epi dissociation; and (4) fractionation. Comparison of these variables was made among the 3 rhythms from an endo–epi perspective. Results Sixteen patients with SHD were included. SRbaseline activations were unicentric and predominantly exited cranially (87.5%) with endo–epi synchrony. However, with overdrive suppression, a tendency for caudal exit shift and endo–epi asynchrony was observed: SRpost-pace600 vs SRbaseline: cranial endo 75% vs 87.5% (P = .046); cranial epi 68.8% vs 87.5% (P = 0.002); caudal endo 12.5% vs 6.2% (P = 0.215); caudal epi 25% vs 6.2% (P = .0003); and SRpost-pace400 vs SRbaseline: cranial endo 81.3% vs 87.5% (P = 0.335); cranial epi 68.7% vs 87.5% (P = 0.0034; caudal endo 12.5% vs 6.2% (P = .148); caudal epi 31.2% vs 6.2% (P = 0.0017), consistent with multicentricity. EGM fractionation was more prevalent with overdrive suppression. Conclusion During mapping of the intact human heart, SAN demonstrated redundancy of sinoatrial exits with postoverdrive shift in sites of earliest activation and epi–endo dissociation of sinoatrial exits.

Background Early degeneration of prosthetic aortic valve in transcatheter aortic valve replacement (TAVR) is a rare complication. Method We report the case of a 75-year-old woman who presented with severe calcific stenosis of Edwards SAPIEN-XT valve implanted only 4 years previously. She is a Jehovah’s Witness and has background of Sjogren’s syndrome with secondary cryoglobulinaemic vasculitis. She was not a suitable candidate for valve-in-valve TAVR in view of early prosthetic valve failure by calcification. Result She underwent surgical explantation of the Sapiens XT valve and mechanical aortic valve replacement. Conclusion To our knowledge, this is the first time that early TAVR valve degeneration and failure of an Edwards SAPIEN-XT valve was reported which required surgical replacement with a mechanical valve.

Summary Background The Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone (MGTX) showed that thymectomy combined with prednisone was superior to prednisone alone in improving clinical status as measured by the Quantitative Myasthenia Gravis (QMG) score in patients with generalised non-thymomatous myasthenia gravis at 3 years. We investigated the long-term effects of thymectomy up to 5 years on clinical status, medication requirements, and adverse events. Methods We did a rater-blinded 2-year extension study at 36 centres in 15 countries for all patients who completed the randomised controlled MGTX and were willing to participate. MGTX patients were aged 18 to 65 years at enrolment, had generalised non-thymomatous myasthenia gravis of less than 5 years' duration, had acetylcholine receptor antibody titres of 1·00 nmol/L or higher (or concentrations of 0·50–0·99 nmol/L if diagnosis was confirmed by positive edrophonium or abnormal repetitive nerve stimulation, or abnormal single fibre electromyography), had Myasthenia Gravis Foundation of America Clinical Classification Class II–IV disease, and were on optimal anticholinesterase therapy with or without oral corticosteroids. In MGTX, patients were randomly assigned (1:1) to either thymectomy plus prednisone or prednisone alone. All patients in both groups received oral prednisone at doses titrated up to 100 mg on alternate days until they achieved minimal manifestation status. The primary endpoints of the extension phase were the time-weighted means of the QMG score and alternate-day prednisone dose from month 0 to month 60. Analyses were by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00294658. It is closed to new participants, with follow-up completed. Findings Of the 111 patients who completed the 3-year MGTX, 68 (61%) entered the extension study between Sept 1, 2009, and Aug 26, 2015 (33 in the prednisone alone group and 35 in the prednisone plus thymectomy group). 50 (74%) patients completed the 60-month assessment, 24 in the prednisone alone group and 26 in the prednisone plus thymectomy group. At 5 years, patients in the thymectomy plus prednisone group had significantly lower time-weighted mean QMG scores (5·47 [SD 3·87] vs 9·34 [5·08]; p=0·0007) and mean alternate-day prednisone doses (24 mg [SD 21] vs 48 mg [29]; p=0·0002) than did those in the prednisone alone group. 14 (42%) of 33 patients in the prednisone group, and 12 (34%) of 35 in the thymectomy plus prednisone group, had at least one adverse event by month 60. No treatment-related deaths were reported during the extension phase. Interpretation At 5 years, thymectomy plus prednisone continues to confer benefits in patients with generalised non-thymomatous myasthenia gravis compared with prednisone alone. Although caution is appropriate when generalising our findings because of the small sample size of our study, they nevertheless provide further support for the benefits of thymectomy in patients with generalised non-thymomatous myasthenia gravis. Funding National Institutes of Health, National Institute of Neurological Disorders and Stroke.

The goal of this study was to describe functional endocardial-epicardial dissociation (FEED), signal complexities, and three-dimensional activation dynamics of the human atrium with structural heart disease (SHD).SHD commonly predisposes to arrhythmias. Although progressive remodeling is implicated, direct demonstration of FEED in the human atrium has not been reported previously.Simultaneous intraoperative mapping of the endocardial and epicardial lateral right atrial wall was performed by using 2 high-density grid catheters during sinus rhythm, pacing drive (600 ms and 400 ms cycle length), and premature extrastimulation (PES). Unipolar electrograms (EGMs) were exported into custom-made software for activation and phase mapping. Difference of ≥20 ms between paired endocardial and epicardial electrodes defined dissociation. EGMs with ≥3 deflections were classified as fractionated.Sixteen patients (mean age 60.5 ± 4.1 years; 18.7% with a history of atrial fibrillation) with SHD (43% ischemia, 57% valvular disease) were included. A total of 9,218 EGMs were analyzed. Compared with sinus rhythm, phase and activation analyses showed significant FEED during pacing at 600 ms and 400 ms (phase mapping 22.4% vs. 10% [p 0.0001] and 25.8% vs. 10% [p 0.0001], respectively; activation mapping 25.4% vs. 7.8% [p 0.0001] and 27.7% vs. 7.8% [p 0.0001]) and PES (phase mapping 34% vs. 10% [p 0.0001]; activation mapping 29.5% vs. 7.8% [p 0.0001]). Fractionated EGMs occurred significantly more during PES compared with sinus rhythm (50.2% vs. 39.5%; p 0.0001). Activation patterns differed significantly during pacing drive and PES, with preferential epicardial exit during the latter (15.9% vs. 13.8%; p = 0.046).Simultaneous endocardial-epicardial mapping revealed significant FEED with signal fractionation and preferential epicardial breakthroughs with PES. Such complex three-dimensional interaction in electrical activation provides mechanistic insights into atrial arrhythmogenesis with SHD.

Objectives This study aimed to determine the spatiotemporal stability of rotors and other atrial activation patterns over 10 min in longstanding, persistent AF, along with the relationship of rotors to short cycle-length (CL) activity. Background The prevalence, stability, and mechanistic importance of rotors in human atrial fibrillation (AF) remain unclear. Methods Epicardial mapping was performed in 10 patients undergoing cardiac surgery, with bipolar electrograms recorded over 10 min using a triangular plaque (area: 6.75 cm 2 ; 117 bipoles; spacing: 2.5 mm) applied to the left atrial posterior wall (n = 9) and the right atrial free wall (n = 4). Activations were identified throughout 6 discrete 10-s segments of AF spanning 10 min, and dynamic activation mapping was performed. The distributions of 4,557 generated activation patterns within each mapped region were compared between the 6 segments. Results The dominant activation pattern was the simultaneous presence of multiple narrow wave fronts (26%). Twelve percent of activations represented transient rotors, seen in 85% of mapped regions with a median duration of 3 rotations. A total of 87% were centered on an area of short CL activity ( Conclusions In patients with longstanding, persistent AF, activation patterns are spatiotemporally stable over 10 min. Transient rotors can be demonstrated in the majority of mapped regions, are spatiotemporally associated with short CL activity, and, when recurrent, demonstrate anatomical determinism.

It is unclear whether the Ross procedure offers superior survival compared with mechanical aortic valve replacement (AVR).This study evaluated experience and compared long-term survival between the Ross procedure and mechanical AVR.Between 1992 and 2016, a total of 392 Ross procedures were performed. These were compared with 1,928 isolated mechanical AVRs performed during the same time period as identified using the University of Melbourne and Australia and New Zealand Society of Cardiac and Thoracic Surgeons' Cardiac Surgery Databases. Only patients between 18 and 65 years of age were included. Propensity-score matching was performed for risk adjustment.Ross procedure patients were younger, and had fewer cardiovascular risk factors. The Ross procedure was associated with longer cardiopulmonary bypass and aortic cross-clamp times. Thirty-day mortality was similar (Ross, 0.3%; mechanical, 0.8%; p = 0.5). Ross procedure patients experienced superior unadjusted long-term survival at 20 years (Ross, 95%; mechanical, 68%; p 0.001). Multivariable analysis showed the Ross procedure to be associated with a reduced risk of late mortality (hazard ratio: 0.34; 95% confidence internal: 0.17 to 0.67; p 0.001). Among 275 propensity-score matched pairs, Ross procedure patients had superior survival at 20 years (Ross, 94%; mechanical, 84%; p = 0.018).In this Australian, propensity-score matched study, the Ross procedure was associated with better long-term survival compared with mechanical AVR. In younger patients, with a long life expectancy, the Ross procedure should be considered in centers with sufficient expertise.

Background The pulmonary veins (PVs) and the PV–LA (left atrium) junction are established sources of triggers initiating atrial fibrillation. In addition, they have been implicated in the maintenance of arrhythmia. Objective To undertake high-density electrophysiological characterization of the right superior PV–LA junction in humans. Methods Mapping was performed in 18 patients without a history of atrial fibrillation undergoing cardiac surgery. A high-density epicardial plaque was positioned at the anterior right superior pulmonary vein covering 3 regions: LA, PV–LA junction, and the PV. Isochronal maps were created during (1) sinus rhythm (SR); (2) LA pacing (LA-Pace); (3) PV pacing (PV-Pace); (4) LA programmed electrical stimulation (LA-PES); and (5) PV programmed electrical stimulation (PV-PES). Regional differences in conduction slowing/conduction block (CS/CB) and the prevalence of fractionated signals (FS) and double potentials (DPs) were assessed. Results A region of isochronal crowding representing CS/CB developed at the PV–LA junction in 84% of the maps. Three distinct activation patterns were seen. Pattern 1: Uniform SR activation without CS/CB. LA-Pace and PES caused 1 to 2 lines of isochronal crowding (CS/CB) at the PV–LA junction. Pattern 2: CS/CB occurred at the PV–LA junction in SR. LA/PV-Pace and LA/PV-PES caused an increase in CS/CB at the PV–LA junction with widely split DPs and FS. Pattern 3: A single incomplete line of CS at the PV–LA junction in SR. With LA/PV pacing and LA/PV-PES, multiple lines (≥3) of CS/CB developed at the PV–LA junction with evidence of circuitous activation and a marked increase in DPs and FS. Conclusion High-density epicardial mapping of the right superior pulmonary vein demonstrates marked functional conduction delay and circuitous activation patterns at the PV–LA junction, creating the substrate for reentry.

Epworth Hospital is the first in the southern hemisphere to acquire the da Vinci Robot to facilitate minimally invasive cardiac surgery. Applications for this new technology include mitral valve repair, atrial septal defect closure, single coronary artery bypass graft to coronary arteries on the front of the heart, ablative surgery for atrial fibrillation and insertion of epicardial pacemaker electrodes. A team of surgeons from the Epworth Hospital have trained at East Carolina University (ECU) Greenville, North Carolina, USA; including surgeons, anesthetists, perfusionist and nurses. Following this, during a week in March, a proctoring surgeon from the USA, Dr. Wiley Nifong, assisted the Epworth team with their initial seven operations, which all proceeded without incident. The initial operative times were longer than the standard surgery, although with additional experience, now totalling 24 patients in all, these times have shortened considerably. The experience to date is summarized as an Addendum to this manuscript.

Background— The pulmonary vein–left atrial (PV–LA) junction is key in pathogenesis of AF, and acute stretch is an important stimulus to AF. We aimed to characterize the response of the junction to acute stretch, hypothesizing that stretch would result in electrophysiological changes predisposing to re-entry. Methods and Results— Fifteen participants undergoing cardiac surgery underwent evaluation of the right superior PV–LA junction using an epicardial mapping plaque. In 10, this was performed before and after atrial stretch imposed by rapid volume expansion, and in 5, it was performed with an intervening observation period. Activation was characterized by conduction slowing and electrogram fractionation transversely across the PV–LA junction, with lines of block also demonstrated perpendicular to the junction. Conduction was decremental (plaque activation time 135.8±46.8 ms with programmed extra stimuli at 10 ms above effective refractory period versus 66.1±22.9 ms with pacing at 400 ms; P P =0.001). Right atrial pressure increased by 2.5±1.8 mm Hg ( P =0.002) with volume expansion. Stretch resulted in conduction slowing across the PV–LA junction (increase in activation time 10.9±14.6 ms in acute stretch group versus −0.1±4.5 ms in control group; P =0.002). Conduction slowing was more marked with programmed extra stimuli at 10 ms above effective refractory period than with stable pacing (13.4±16.5 ms versus 1.7±5.4 ms; P =0.003). Stretch resulted in a significant increase in fractionated electrograms (7.9%±7.0% versus −0.4±3.3; P =0.004). Conclusions— Acute stretch results in conduction slowing across the PV–LA junction, with a greater degree of signal complexity. This substrate may be important in AF initiation and maintenance by promoting re-entry.

OBJECTIVE To report on the initial results of minimally invasive direct coronary artery bypass surgery (MIDCAB) without cardiopulmonary bypass. This is a potential alternative to conventional coronary artery bypass graft surgery, recently introduced to Australia. DESIGN Prospective survey of patient data. SETTING Royal Melbourne Hospital campus, Melbourne, Victoria, July 1996 to June 1997. PATIENTS The first 23 consecutive patients to have a MIDCAB procedure without cardiopulmonary bypass via a small left thoracotomy. The left anterior descending coronary artery was revascularised with the left internal mammary artery. All patients had either recurrent stenosis after previous angioplasty or anatomy unsuitable for angioplasty. OUTCOME MEASURES Operative morbidity and mortality; graft patency; and patient symptom relief and reoperation rates. RESULTS Mean age of patients was 57.9 years (range, 29-81), and mean follow-up was 4.0 months (range, 1-10). There was no operative mortality, cardiac infarction or stroke. Mean postoperative stay in the Intensive Care Unit was 30.7 hours and in hospital, 5.3 days. Only one patient needed a blood transfusion (packed red cells). Initial patency of the grafts was confirmed by either angiography (five) or continuous pulse-wave Doppler (23). One patient underwent angioplasty for a stenosis distal to the anastomosis, and two patients (9%) required reoperation for recurrent angina. CONCLUSIONS MIDCAB can be performed safely, and patient recovery is faster than after conventional coronary artery surgery.

OBJECTIVE: To examine the effects of cardiopulmonary bypass (CPB) on total and unbound plasma concentrations of propofol and midazolam when administered by continuous infusion during cardiac surgery. DESIGN: Prospective clinical study. SETTING: University hospital. PARTICIPANTS: Twenty-four adult patients undergoing cardiac surgery. INTERVENTIONS: Patients received either propofol or midazolam to supplement fentanyl anesthesia. Twelve patients received a propofol bolus (1 mg/kg) followed by an infusion of 3 mg/kg/hr. A second group received midazolam, 0.2 mg/kg bolus, followed by an infusion of 0.07 mg/kg/hr. MEASUREMENTS AND MAIN RESULTS: Blood sample were collected from the radial artery cannula at 0, 2, 4, 8, 8, 10, 15, 20 minutes and then every 10 minutes before CPB, at 1, 2, 3, 4, 6, 10, 15, 20 minutes and then each 10 minutes during CPB. On weaning from CPB samples were collected at 0, 5, 10 and 20 minutes. Plasma binding, total and unbound propofol and midazolam concentrations were determined by ultrafiltration and high-pressure liquid chromatography (HPLC). CPB resulted in a fall in total propofol and midazolam plasma concentrations, but the unbound concentrations remained stable. The propofol unbound fraction increased from 0.22 +/- 0.06% to 0.41 +/- 0.17%. The midazolam unbound fraction increased from 5.6 +/- 1.0% to 11.2 +/- 2.1%. CONCLUSIONS: Unbound concentrations of propofol and midazolam are not affected by cardiopulmonary bypass. Total intravenous anesthesia algorithms do not need to be changed to achieve stable unbound plasma concentrations when initiating CPB.

Secondary mediastinal tumours are rare. We present a case report of multiple mediastinal metastasis of ovarian cancer, a very rare occurrence with only two cases previously reported in the literature.

Objectives To characterize the nature of atrial fibrillation (AF) activation in human persistent AF (PerAF) using modern tools including activation, directionality analyses, complex-fractionated electrogram, and spectral information. Background The mechanism of PerAF in humans is uncertain. Methods and results High-density epicardial mapping (128 electrodes/6.75 cm2) of the posterior LA wall (PLAW), LA and RA appendage (LAA, RAA), and RSPV-LA junction was performed in 18 patients with PerAF undergoing open heart surgery. Continuous 10 s recordings were analysed offline. Activation patterns were characterized into four subtypes (i) wavefronts (broad or multiple), (ii) rotational circuits (≥2 rotations of 360°), (iii) focal sources with centrifugal activation of the entire mapping area, or (iv) disorganized activity [isolated chaotic activation(s) that propagate ≤3 bipoles or activation(s) that occur as isolated beats dissociated from the activation of adjacent bipole sites]. Activation at a total of 36 regions were analysed (14 PLAW, 3 RSPV-LA, 12 LAA, and 7 RAA) creating a database of 2904 activation patterns. In the majority of maps, activation patterns were highly heterogeneous with multiple unstable activation patterns transitioning from one to another during each recording. A mean of 3.8 ± 1.6 activation subtypes was seen per map. The most common patterns seen were multiple wavefronts (56.2 ± 32%) and disorganized activity (24.2 ± 30.3%). Only 2 of 36 maps (5.5%) showed a single stable activation pattern throughout the 10-s period. These were stable planar wavefronts. Three transient rotational circuits were observed. Two of the transient circuits were located in the posterior left atrium, while the third was located on the anterior surface of the LAA. Focal activations accounted for 11.3 ± 14.2% of activations and were all short-lived (≤2 beats), with no site demonstrating sustained focal activity. Conclusion Human long-lasting PerAF is characterized by heterogeneous and unstable patterns of activation including wavefronts, transient rotational circuits, and disorganized activity.

A year-old woman presented with heart failure six weeks after acute right coronary artery angioplasty and pacemaker for an inferior myocardial infarction. A ventricular septal defect (VSD)was diagnosed on echocardiography, and she was referred to our institution for closure. Repeat transthoracic echocardiography demonstrateda small basal inferiorwall aneurysm,witha rupture point at the apex of the aneurysm (Supplementary matethrough the interventricular septum (Fig. 1A and B). Postoperative recovery was uneventful, with discharge home on day five. Post infarct VSD is uncommon, but an important differential for any patient presenting with post infarct heart failure. Usually, the VSD presents within the first week post infarct, though later presentations, such as our case, have been described. rial). Colour Doppler showed that the path of rupture was within the ventricular septal wall prior to exiting into the right ventricle. Following angiography (Supplementarymaterial), she proceeded to open repairwith a 2-patch approach through the right atrium and a single bypass to the right coronary artery. Intra-operative 2D and 3D transoesophageal echocardiography confirmed the tunnel Appendix A. Supplementary data

FIGURE 1. Computed tomography scans. Long-axis images show dense calcification attached to the left ventricular endocardium and mitral annulus. LA, Left atrium; LV, left ventricle; A, Anterior; P, posterior; X, calcific mass. CLINICAL SUMMARY A 75-year-old woman presented with episodic presyncope associated with palpitations. She was diabetic and hypertensive with a history of rheumatic fever with associated valvular dysfunction. Physical examination revealed an irregular pulse rate of 82 beats/min and no signs of left heart failure. On auscultation, a soft diastolic murmur was heard. Biochemical investigation results were all within normal limits, including serum calcium, parathormone levels, and proteins C and S. Electrocardiography confirmed atrial fibrillation and showed periods of sinus rhythm and firstdegree heart block. In-hospital telemetry demonstrated episodes of complete heart block rate that required permanent pacemaker. Transthoracic and transesophageal echocardiography showed the presence of a large echogenic mass at the basal inferior wall and inferoposterior mitral annulus extending into both the interventricular and interatrial septae. The mass appeared encapsulated, intramyocardial, and extensive (5.4 3 4.2 cm). The posterior mitral valve leaflet was clearly compressed by the mass, causing mild mitral stenosis and mild mitral regurgitation. Left ventricular function was preserved. Transthoracic echocardiography, performed 3 years previously to investigate a diastolic murmur, revealed a 2.5 3 1.8-cm calcific mass behind the posterior mitral valve leaflet. The patient was lost to follow-up. Computed tomography (Figure 1) of the chest and cardiac magnetic resonance imaging confirmed the presence

Left ventricular (LV) rupture is an uncommon catastrophic complication post myocardial infarction. We describe 2 rare cases of LV rupture complicating inferior ST Elevation Myocardial Infarction (STEMI) causing right ventricular (RV) intramyocardial dissection with left-to-right shunting.

Background Off-pump coronary artery bypass grafting (OPCAB) is associated with a less intense systemic inflammatory response according to biochemical markers. We studied systemic vascular resistance (SVR) as a physiologic response to systemic inflammatory response to determine any differences between OPCAB and on-pump coronary artery bypass grafting (ONCAB) in a prospective randomized trial. Methods One hundred consecutive patients were randomized to OPCAB or ONCAB, 50 in each group. Antifibrinolytics and steroids were not used. All protocols were identical except for cardiopulmonary bypass. Temperature, SVR index, cardiac index, and blood pressure were measured continuously for the first 24 hours postoperatively. All patients were reviewed at 30 days. Results There was no 30-day mortality, no stroke, and no acute renal failure. Mean temperature peaked at 37.5°C at 12 hours ( p = 0.700 between groups). Mean SVR index fell to 1,900 dyne·cm −5 ·m −2 at 12 to 18 hours; 42% of OPCAB and 32% of ONCAB patients developed very low SVR index ( −5 ·m −2 ). The incidence of high SVR (>2,500 dyne·cm −5 ·m −2 ) fell from 20% to 2% by 12 to 18 hours. The extent and pattern of SVR index responses were similar in both groups ( p = 0.840). Mean cardiac index peaked at 3.0 L·min −1 ·m −2 , 12 to 18 hours postoperatively ( p = 0.815 between groups); 84% of OPCAB and 90% of ONCAB had cardiac index greater than 2.2 L·min −1 ·m −2 at all times. Only 10% of patients required vasopressors. Blood pressure responses were also similar ( p = 0.314). Conclusions The incidence of low SVR, and patterns of SVR changes were similar in ONCAB and OPCAB, and were clinically unimportant as few patients required vasopressor support. Cardiac outputs and clinical outcomes were excellent in both groups.

Background Thoracic aortic transection resulting from blunt trauma is usually fatal. It is almost always associated with multiple, complex, nonaortic injuries that could be adversely affected by standard surgical repair of the aorta. Endovascular stenting techniques offer these patients a less physiologically disruptive treatment option. We studied the feasibility and safety of endovascular stent graft placement for treatment of acute traumatic aortic transection. Methods Between 1994 and 2001, 9 patients were treated emergently for aortic transections with stent graft placement. The first patient had a custom-made prototype, and the other 8 patients had the Cook-Zenith thoracic stent graft implanted. All were polyester-covered Z-stent construction and deployed through a femoral 20- to 24-F delivery sheath. Results Stent graft placement successfully sealed the aorta in all patients. One patient died as a result of a cerebrovascular accident. One patient required a brachial thrombectomy to relieve arm ischemia. The remaining eight patients were alive and without complications during the follow-up period (mean 21 months). Conclusions Endovascular repair for acute aortic transection is a safe, effective, and timely treatment option. It may be the treatment of choice in patients with extensive associated injuries.