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A 70-year-old female with exertional dyspnoea was found to have basal septal hypertrophy (BSH), or a ‘basal septal bulge’, with evidence of mild left ventricular outflow tract obstruction (LVOT) at rest on her initial echocardiogram. She was usually fit and well with no significant past medical history. She had no history of hypertension. She had never smoked. There was no family history of hypertrophic cardiomyopathy (HCM). A cardiac MRI did not demonstrate any typical features of HCM. ECG showed sinus tachycardia with a rate of 101 bpm but was otherwise unremarkable. She was referred for exercise echocardiography to assess for latent LVOT obstruction. Prior to commencing exercise, her LVOT gradient was re-assessed at rest. Her LVOT gradients were 30 mmHg at rest, 49 mmHg during Valsalva and 91 mmHg on standing. A diagnosis of significant latent LVOT obstruction was made and the patient was started on bisoprolol, a cardioselective beta-blocker. Bisoprolol was slowly uptitrated from 1.25 mg to 5 mg once daily, following which the patient reported a significant improvement in her symptoms with an improved exercise capacity. Follow-up echocardiography demonstrated a dramatic reduction in LVOT gradient, with a maximum of 11 mmHg assessed both with Valsalva and on standing. This case is a reminder that patients with a ‘common’ basal septal bulge can develop significant LVOT obstruction, the symptoms of which may respond to pharmacological therapy. Orthostatic assessment of LVOT gradient using echocardiography should be considered during standard LVOT obstruction provocation manoeuvres such as a Valsalva.

Objective: ECG ST segment resolution (STR) has been used to assess myocardial perfusion in STEMI patients undergoing PPCI. However, in most of the studies ECGs recorded at different time points after the actual procedure have been used, limiting the options of therapeutic interventions while the patient is still in the catheterisation laboratory. The aim of this study was to investigate the presence and clinical consequences of intra-procedural STR during PPCI.Methods: We analysed 12 lead ECGs recorded at the onset and the end of the PPCI procedure, measuring STR in the lead with maximum ST elevation on the initial recording. STR was defined as good when > 50% compared to baseline.Results: Pre and immediately post PPCI ECGs were recorded in 467 STEMI cases whilst the patient was on the catheter lab table. Mean patient age was 63 (+/- 12) years old and 75% were men. Mean duration of symptoms to admission was 3.8 (+/- 3.4) hours and 51% of infarcts were anterior. Good ST resolution at the end of the procedure was seen in 46.5% of patients and was observed more commonly in inferior compared to anterior infarcts (60.1% vs. 32.6%, p<0.001), and in current smokers (53.2% vs. 42.4%, p=0.031). In patients presenting with symptoms for < 4 hours, good STR was more common (74% vs. 66%, p=0.019). Thrombus aspiration was used more frequently in patients who had good STR (88.5% vs 79.8% p=0.011). Patients with good ST resolution had a shorter mean hospital length of stay (3.8 vs. 4.5 days, p=0.009) and a higher left ventricular ejection fraction (49.9% vs. 44.2%, p<0.001) measured by transthoracic echocardiography prior to discharge.Conclusion: Good peri-procedural ST resolution was seen in less than half of STEMI patients undergoing PPCI. There were important clinical consequences of good ST resolution. Identification of suboptimal peri-procedural ST resolution could help identify patients who may benefit from new treatments aimed at protecting the microcirculation, whilst the patients are still in the angiography laboratory. [ABSTRACT FROM AUTHOR]

Complex blade responses such as a rotating stall or simultaneous resonances are common in modern engines and their observation can be a challenge even for state-of-the-art tip-timing systems and trained operators. This paper analyses forced vibrations of axial compressor blades, measured during the bench tests of the SO-3 turbojet. In relation to earlier studies conducted in Poland with a small number of sensors, a multichannel tip-timing system let us observe simultaneous responses or higher-order modes. To find possible symptoms of a failure, blade responses in a healthy and unhealthy engine configuration with an inlet blocker were studied. The used analysis methods covered all-blade spectrum and the circumferential fitting of blade deflections to the harmonic oscillator model. The Pearson coefficient of correlation between the measured and predicted tip deflection is calculated to evaluate fitting results. It helps to avoid common operator mistakes and misinterpreting the results. The proposed modal solver can track the vibration frequency and adjust the engine order on the fly. That way, synchronous and asynchronous vibrations are observed and analysed together with an extended variant of least squares. This approach saves a lot of work related to configuring the conventional tip-timing solver.

Background: ST segment elevation allows the rapid identification of patients with acute myocardial infarction who benefit from emergency reperfusion. Primary percutaneous coronary intervention (PPCI) has emerged as the preferred perfusion strategy for patients presenting with ST segment elevation myocardial infarction (STEMI)., Methods and Results: We studied the effects of the simple passage of an angioplasty guidewire followed by mechanical thrombus aspiration on the ST segment displacement in 289 patients presenting with acute STEMI. Simple guidewire passage led to a statistically significant fall in the mean ST elevation from 5.9 to 4.9 mm (p<0.001), but the mean ST displacement after subsequent mechanical thrombus aspiration was 4.8 mm, not statistically significantly different from guidewire passage. When compared with simple guidewire passage, thrombus aspiration resulted in more patients achieving more than 50% ST resolution (21.8% vs 15.2%, p=0.009), but a higher proportion had a worsening of ST elevation compared to baseline (19.7% vs 13.5%, p=0.041)., Conclusions: Mechanical thrombus aspiration in acute STEMI did not improve the mean ST resolution compared with simple guidewire passage. Thrombus aspiration increased the proportion achieving 50% resolution but also increased the proportion who had a worsening of ST elevation. These data may help explain some of the uncertainties surrounding the routine use of thrombus aspiration in STEMI and potentially supports the use of 'time to angioplasty guidewire passage' as one of the ways to judge the promptness of PPCI services.

Structural failure of mechanical heart valves is associated with a high mortality, especially when the valve is implanted in the aortic position. We describe a case of early intermittent dysfunction of a bileaflet mechanical heart valve implanted in a 67-year-old female. Transthoracic and transoesophageal echocardiography demonstrated intermittent jamming of the leaflets in both the open and closed positions in the absence of any obvious obstruction. The reason for the dysfunction was unclear. This intermittent dysfunction was thought to be a result of dynamic distortion of the pivot guards during the cardiac cycle.