Jonathan Timperley

Transthoracic echocardiography using second harmonic imaging with Valsalva manoeuvre for the detection of right to left shunts

AIMS To assess transthoracic echocardiography (TTE) using second harmonic imaging with Valsalva manoeuvre compared to transesophageal echocardiography (TEE) for the diagnosis of right to left cardiac and pulmonary shunts. METHODS AND RESULTS One hundred and ten patients referred for TEE underwent TTE with bubble contrast. Bubbles in the left atrium within three cardiac cycles were considered diagnostic for a patent foramen ovale (PFO) and later as a pulmonary shunt. Greater than 20 bubbles in the left atrium was considered a large shunt and less than 20 a small shunt. TEE was performed immediately afterwards and read blinded to the TTE results. Pick-up rates were similar with 19 TEE positive (13 PFO) and 18 TTE positive (14 PFO) patients. There were five TEE positive/TTE negative cases who had significantly poorer TTE image quality score (2.7 +/- 0.8 vs 1.9 +/- 0.6, p < 0.05). There were six TEE negative/TTE positive cases, two cases requiring Valsalva manoeuvre to become positive. The Valsalva manoeuvre significantly increased the number of bubbles shunting (10 +/- 11 vs 20 +/- 19, p < 0.005). CONCLUSION TTE with Valsalva manoeuvre is as good as TEE in diagnosing shunts. Valsalva manoeuvre increases the size of shunt. Both techniques produce false negative results.

Flecainide overdose--support using an intra-aortic balloon pump.

BackgroundFlecainide is an antiarrhythmic agent which is being used increasingly for the management of super-ventricular arrhythmias. Overdose with flecainide is frequently fatal with mortality reported as high as 22% due to arrhythmias, myocardial depression and conduction defects leading to electro-mechanical dissociation and asytole. Supportive measures are often required during the case and previously have included inotropes, extracorporeal membrane oxygenation and cardiopulmonary bypass.Case presentationA 47 year old lady presented to the emergency department with a four hour history of severe central chest pain. Her ECG showed atrial fibrillation and broad QRS complexes with a sine wave appearance. She had a past history of paroxysmal atrial fibrillation and significant psychiatric history. Following thrombolysis for a presumed myocardial infarction she developed cardiogenic shock with severely impaired left ventricular function. An intra-aortic balloon pump was inserted and coronary angiography demonstrated normal coronary arteries. With inotropic support she improved over 48 hours, with both her QRS duration and left ventricular function returning to normal. Biochemical testing following her discharge demonstrated significantly elevated levels of flecainide.ConclusionThe use of an intra-aortic balloon pump is a useful supportive measure during the acute phase of flecainide overdose associated with severe myocardial depression.

Echocardiographic assessment and percutaneous closure of multiple atrial septal defects.

Atrial septal defect closure is now routinely performed using a percutaneous approach under echocardiographic guidance. Centrally located, secundum defects are ideal for device closure but there is considerable morphological variation in size and location of the defects. A small proportion of atrial septal defects may have multiple fenestrations and these are often considered unsuitable for device closure. We report three cases of multiple atrial septal defects successfully closed with two Amplatzer septal occluders.

Natural history of intramural hematoma of the descending thoracic aorta

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Changes in Intrathoracic Impedance from a Pneumothorax: Insights from an Implanted Monitoring System

The measurement of transthoracic impedance is now possible using new implantable cardioverter‐defibrillators. This can be used to monitor fall in impedance associated with increasing pulmonary oedema. We describe a case of a large rapid increase of impedance and dyspnoea related to a pneumothorax.

Late emergence of platypnea orthodeoxia: Chiari network and atrial septal hypertrophy demonstrated with transoesophageal echocardiography

Platypnea orthodeoxia is a rare syndrome that describes breathlessness on standing that resolves on lying flat. We present a previously healthy patient who developed platypnea orthodeoxia in her eighth decade of life. Cardiovascular imaging demonstrated an atrial septal defect, extensive Chiari network and atrial septal hypertrophy. We propose the development of lipomatous atrial septal hypertrophy led to altered atrial compliance and a baffle to direct flow preferentially to the left heart on standing.

Current indications for contrast echocardiography imaging.

UNLABELLED The assessment of regional ventricular function is dependent on good endocardial definition. Suboptimal images can be converted to diagnostic recordings in the majority of patients by contrast agents, which have become an indispensable aid in rest and stress echocardiography. In particular for stress echocardiography image quality is essential and contrast administration is of great importance. However this diagnostic procedure must be performed following the indications which reflect the risks of the procedure and consider the benefits of an accurate diagnosis on further patient management. The contraindications recently introduced in the use of the echo-contrast agent SonoVue for acute cardiac patients reflect the same contraindications which have been applied in stress echocardiography for several years. Clinical trials and post-marketing surveillance have demonstrated that this approach is safe with no fatalities reported. For all ultrasound contrast media, side effects have been reported but they are usually mild. However, rare allergic and potentially life threatening reactions may occur and the investigators have to be prepared for such an event with appropriate drugs stored in the echo department. In a recent retrospective analysis in 751 consecutive stress echocardiograms the use of contrast during dobutamine stress echocardiography was not associated with an increased risk of side effects. The incidence of side effects was very low and different in patients receiving Optison, SonoVue or without contrast agent. CONCLUSION Ultrasound contrast agents are licensed for improvement of endocardial border definition. Data from clinical trials and wide clinical experience indicate an excellent risk/benefit ratio if the current contraindications are applied.

Prognosis of Aortic Intramural Hematoma With and Without Penetrating Atherosclerotic Ulcer: A Clinical and Radiological Analysis

To the Editor: We agree with Ganaha et al1 that differentiation between the distinct clinical entities of intramural hematoma (IMH) and penetrating atherosclerotic ulcer (PAU) is essential. Hemorrhage occurs within the aortic wall during IMH despite a nonatheromatous intact intima, whereas secondary medial hemorrhage occurs through an atheromatous disrupted intima in patients with …

Contrast echocardiography for left ventricular opacification.

Echocardiography has been criticised of having only moderate reproducibility and of having a low sensitivity of changes in left ventricular ejection fraction (LVEF). Inadequate endocardial visualisation during echocardiography occurs in up to 20% of cases. Although image quality has been improved with the introduction of harmonic imaging,1,2 there are still a number of studies remaining of inadequate quality, and it is here that the use of contrast agents comes into its own.3 A number of studies have now been performed looking at the effect of contrast on assessment of cardiac regional and global function. This paper reviews the current and future clinical use of ultrasound contrast agents for assessment of left ventricular function. The first licensed contrast agent in the UK was Levovist (Schering, Germany) and has now been followed by Optison (Amersham, UK) and Sonovue (Bracco, Italy) which are licensed for left ventricular opacification. Although infusions are preferential for assessment of myocardial perfusion, bolus injections of agents may be satisfactory for left ventricular opacification in many cases. In tandem with the development of contrast agents have been advances in imaging modalities. The first contrast specific modalities were harmonic imaging and harmonic power Doppler, which both use a relatively high transmit power leading to bubble destruction. Optimal imaging therefore requires triggered imaging. Second harmonic imaging enhances contrast effect compared to fundamental imaging and has been used for border definition using real-time imaging.4 However, it also leads to bubble destruction and artefacts. Latest developments such as power modulation and power pulse inversion, which are low power techniques and non-destructive, allow for real-time imaging without the limitations of harmonic imaging and with less contrast. As tissue returns are not displayed, unlike with …

Heart Within a Heart Contrast 3-Dimensional Echocardiography Imaging of a Tricuspid Valve Blood Cyst

An 80-year-old woman was referred with non-sustained palpitations, intermittent presyncope, and atypical chest pain. Examination revealed a loud “plopping” first heart sound and presystolic thrill at the lower left sternal edge. Echocardiography showed a large cystic lesion attached to the septal leaflet of the tricuspid valve, dilatation of the right heart chambers, and moderate tricuspid regurgitation (Figure 1). Three-dimensional contrast echocardiography confirmed the mobile cyst and revealed small lesions within it (Figure 2a); during systole, the cyst became deformable within the ventricle, resulting in a “heart” shape (Figure 2b). The following day, her clinical findings had changed, with loss of the “plopping” first heart sound, a new systolic murmur at the left sternal edge, and loss of the presystolic thrill. Echocardiography confirmed cyst migration into the right ventricular outflow tract with partial obstruction (Figure 3). Emergency resection on cardiopulmonary bypass revealed a blood-filled cyst with small interior cysts that was attached to the tricuspid valve. Histological examination confirmed a simple blood-filled cyst. The patient had an uncomplicated recovery. Blood -filled cysts are typically small and asymptomatic and are most commonly found in infants. In most cases, they regress spontaneously and are rare in adults, but they occasionally obstruct, as in this case.An 80-year-old woman was referred with non-sustained palpitations, intermittent presyncope, and atypical chest pain. Examination revealed a loud “plopping” first heart sound and presystolic thrill at the lower left sternal edge. Echocardiography showed a large cystic lesion attached to the septal leaflet of the tricuspid valve, dilatation of the right heart chambers, and moderate tricuspid regurgitation (Figure 1). Three-dimensional contrast echocardiography confirmed the mobile …