Patency When Grafted to Coronary Stenosis More Than 50% in LIMA-RA-Y Grafts.

BACKGROUND: Recent coronary surgery practice is to graft arterial conduits to more severely stenosed coronary targets than in the past. We aimed to investigate postoperative arterial graft patency with native coronary stenosis at the time of surgery, using the left internal mammary artery and radial artery (RA) as a composite Y graft (LIMA-RA-Y). In the study timeframe, it was routine clinical practice to graft coronary arteries with >50% stenosis. METHODS: Of 464 patients previously reported 1996-1999, 346 who underwent LIMA-RA-Y at the Royal Melbourne Hospital, 76 had postoperative angiograms at the same institution. Each anastomosis was considered separately. For arterial grafts a "string sign" was analysed as being occluded. Predictor of patency was performed with a generalised linear mixed model (GLMM). RESULTS: Seventy-six (76) patients had postoperative angiograms at 5.8±5.4 years (range 0.23-19.4; interquartile range 1.7-10.0) years postoperative; with age at operation 62.5±10.7 years and 3.4±0.8 grafts per patient, 82% were male. Of 256 anastomoses, 230 were to coronary targets >50% stenosis. Overall patency was 84.0% (214/256). For coronary stenosis >50%, patency was 88% (201/230) and varied by coronary territory left anterior descending (LAD) 94% (87/93), circumflex 90% (71/79) and right coronary artery (RCA) 74% (43/58). Interaction for coronary territory was significant (p=0.022). Higher preoperative coronary stenosis predicted higher patency; with odds ratio for improved patency of 1.83 (95% CI 1.51, 2.22), p<0.001 for each 10% increase in stenosis. CONCLUSIONS: Late patency of composite arterial grafts is acceptable when grafted to coronary arteries of greater than 50% stenosis.

Impact of the Cox-Maze IV Procedure on Left Atrial Mechanical Function.

BACKGROUND: The Cox-Maze IV procedure is a proven surgical treatment for atrial fibrillation (AF). Previous studies on the procedure and its effect on left atrial mechanical function have yielded mixed results. METHODS: Sixty-four (64) patients underwent Cox-Maze IV at St Vincent's Hospital, Melbourne between March 2010 and May 2016. Baseline characteristics were collected and outcomes assessed including rhythm analysis. Preoperative and postoperative transthoracic echocardiograms were reviewed. RESULTS: Fifty-seven (57) patients had complete follow-up with all clinical measures collected. The mean age was 71.1±10.2years, 63% being male. Fifty-eight per cent (58%) (33/57) of patients were in AF and 42% (24/57) in sinus rhythm (SR) at preoperative transthoracic echocardiography. Follow-up postoperative transthoracic echocardiography was performed at a mean of 2.3±1.9years. Nineteen (19) patients with a history of paroxysmal AF were in SR both preoperatively and postoperatively. In these patients, there was a significant decrease in Mitral A wave 0.63±0.28m/s (pre-op) vs 0.47±0.29m/s (post-op), p=0.044. There was a significant decrease in left ventricular ejection fraction (LVEF) postoperatively 64.2±9.7% vs 55.0±12.9%, p=0.005. At follow-up, 28% (16/57) were in AF, 61% (35/57) in SR, and 11% (6/57) in a paced rhythm. In a multivariate analysis, predictors of AF recurrence included higher LA volumes (p=0.042) and younger age at surgery p=0.030. Preoperative AF, sex and LVEF had no impact on AF recurrence. CONCLUSIONS: The Cox-Maze IV procedure, while effective in converting patients to sinus rhythm, may reduce left atrial mechanical function in patients with paroxysmal AF.

A Pilot Assessment of 3 Point-of-Care Strategies for Diagnosis of Perioperative Lung Pathology.

BACKGROUND: Lung ultrasonography is superior to clinical examination and chest X-ray (CXR) in diagnosis of acute respiratory pathology in the emergency and critical care setting and after cardiothoracic surgery in intensive care. Lung ultrasound may be useful before cardiothoracic surgery and after discharge from intensive care, but the proportion of significant respiratory pathology in this setting is unknown and may be too low to justify its routine use. The aim of this study was to determine the proportion of clinically significant respiratory pathology detectable with CXR, clinical examination, and lung ultrasound in patients on the ward before and after cardiothoracic surgery. METHODS: In this prospective observational study, patients undergoing elective cardiothoracic surgery who received a CXR as part of standard care preoperatively or after discharge from the intensive care unit received a standardized clinical assessment and then a lung ultrasound examination within 24 hours of the CXR by 2 clinicians. The incidence of collapse/atelectasis, consolidation, alveolar-interstitial syndrome, pleural effusion, and pneumothorax were compared between clinical examination, CXR, and lung ultrasound (reference method) based on predefined diagnostic criteria in 3 zones of each lung. RESULTS: In 78 participants included, presence of any pathology was detected in 56% of the cohort by lung ultrasound; 24% preoperatively and 94% postoperatively. With lung ultrasound as a reference, the sensitivity of the 5 different pathologies ranged from 7% to 69% (CXR), 7% to 76% (clinical examination), and 14% to 94% (combined); the specificity of the 5 different pathologies ranged from 91% to 98% (CXR), from 90% to 99% (clinical examination), and from 82% to 97% (combined). For clinical examination and lung ultrasound, intraobserver agreements beyond chance ranged from 0.28 to 0.70 and from 0.84 to 0.97, respectively. The agreements beyond chance of pathologic diagnoses between modalities ranged from 0.11 to 0.64 (CXR and lung ultrasound), from 0.08 to 0.7 (CXR and lung ultrasound), and from 0 to 0.58 (clinical examination and CXR). CONCLUSIONS: Clinically important respiratory pathology is detectable by lung ultrasound in a substantial number of noncritically ill, pre or postoperative cardiothoracic surgery participants with high estimate of interobserver agreement beyond that expected by chance, and we showed clinically significant diagnoses may be missed by the contemporary practice of clinical examination and CXR.

Calcified left ventricular apical aneurysm with intramural thrombus: a case report.

Background: Left ventricular aneurysms (LVAs) are a well-appreciated complication of acute myocardial infarction. Ventricular aneurysms involving the left ventricle (LV) typically evolve as a result of anterior myocardial infarction and are associated with greater morbidity, complication rates, and hospital resource utilization. Incidence of LVA is decreasing with advent of modern reperfusion therapies; however, in the setting of excess morbidity, clinicians must maintain an appreciation for their appearance to allow timely diagnosis and individualized care. Case summary: This case report describes the clinical history, investigation, appearance, and management of a patient with calcified apical LVA with history of previous anterior ST-elevation myocardial infarction. The patient was initially admitted for elective coronary angiography in the setting of worsening exertional dyspnoea and subsequently underwent coronary artery bypass graft, aneurysm resection, and LV reconstruction. Discussion: Left ventricular aneurysms are an uncommon complication experienced in the modern era of acute myocardial infarction and current reperfusion therapies, but remain an important cause of excess morbidity and complication. Evidence-based guidelines for the diagnosis, workup, and subsequent management of LVAs are lacking. The imaging findings presented in this case serve as an important reminder of the appearance of LVAs so that timely diagnosis and individualized care considerations can be made.

Pericardial decompression syndrome with acute right ventricular failure: a case series.

Background: Pericardial decompression syndrome (PDS) is an uncommon complication of pericardial drainage of large pericardial effusions and cardiac tamponade characterized by paradoxical haemodynamic instability following drainage. Pericardial decompression syndrome may occur immediately, or in the days following pericardial decompression, and presents with signs and symptoms suggestive of uni-/biventricular failure or acute pulmonary oedema. Case summary: This series describes two cases of this syndrome which demonstrates acute right ventricular failure as a mechanism of PDS and provides insights into the echocardiographic findings and clinical course of this poorly understood syndrome. Case 1 describes a patient who underwent pericardiocentesis, whilst Case 2 describes a patient who underwent surgical pericardiostomy. In both patients, acute right ventricular failure was observed following the release of tamponade and is favoured to be the cause of haemodynamic instability. Discussion: Pericardial decompression syndrome is a poorly understood, likely underreported complication of pericardial drainage for cardiac tamponade associated with high morbidity and mortality. Whilst a number of hypotheses exist as to the aetiology of PDS, this case series supports haemodynamic compromise being secondary to left ventricular compression following acute right ventricular dilatation.

21-Year Survival of Left Internal Mammary Artery-Radial Artery-Y Graft.

BACKGROUND: In 1999, Royse et al. reported on the left internal mammary artery, radial artery, Y-graft technique (LIMA-RA-Y), which achieves total arterial revascularization (TAR). However, the most common coronary reconstruction remains LIMA and supplementary saphenous vein grafts (LIMA + SVG). OBJECTIVES: The goal of this study was to conduct a survival comparison of LIMA-RA-Y versus the conventional LIMA + SVG. METHODS: Of the original 464 LIMA-RA-Y patients reported (1996 to 1998), 346 were from the Royal Melbourne Hospital. Survival at June 2017 was compared with a group of 534 patients from 1996 to 2003 from the same institution who received LIMA + SVG, or 5,800 patients who received TAR with different grafting configurations. Propensity score matching (PSM) was performed with 1:1 matching using 26 variables. Comparisons used Kaplan-Meier (KM) and Cox proportional hazards methods. LIMA-RA-Y was compared with LIMA + SVG in which all non-left anterior descending artery grafts were performed with either composite RA or aorta-coronary SVG with no use of right internal mammary artery. We also conducted a comparison of LIMA-RA-Y versus TAR. RESULTS: Baseline characteristics of the LIMA-RA-Y group (n = 346) compared with LIMA + SVG (n = 534) after PSM (n = 232 pairs) did not differ (3.3 ± 0.8 grafts per patient). Survival was worse for LIMA + SVG in the unmatched groups (KM, p < 0.001) and for PSM groups (KM, p = 0.043; Cox proportional hazards ratio: 1.3; 95% confidence interval: 1.0 to 1.6; p = 0.038). Survival did not differ between LIMA-RA-Y and other TAR (n = 5,800) patients before, or after, PSM (n = 332 pairs). CONCLUSIONS: Use of LIMA + SVG has worse survival than LIMA-RA-Y in achieving total arterial revascularization.