Echocardiography for the clinician: a practical update

Echocardiography is the mainstay of cardiovascular diagnostics, and is the most performed test for the evaluation of cardiac function. Critical and costly management decisions are based on quantification of left ventricular volumes and ejection fraction. Recent advances in echocardiography, such as microsphere contrast echocardiography for left ventricular opacification and perfusion imaging, three-dimensional transthoracic and trans-oesophageal imaging, strain and tissue Doppler imaging, all contribute to improving accuracy and reproducibility of these important measurements. Such techniques are now routinely available on standard echocardiography equipment in Australian centres for daily use. Hand-carried ultrasound devices have been developed, which are portable, are affordable and offer increased availability of echocardiography to the wider community. Clinicians should be actively encouraged to adopt these technologies to improve the diagnostic quality and reproducability of echocardiography for our patients. This article provides an overview of important recent advances in echocardiographic imaging with an emphasis on their role in clinical practice today.

Direct visualization of septal perforator coronary arterial blood flow during perflutren microsphere contrast echocardiography

A 62-year-old female with supraventricular tachycardia underwent a contrast echocardiogram to assess left ventricular structure and function due to sub-optimal images on conventional imaging. Multi-pulse, phase inversion, low mechanical index imaging was used (left ventricular opacification), combined with bolus dosing of a perflutren microsphere (Definity). In the parasternal short-axis view, during contrast imaging, flow within a septal coronary artery could be directly visualized. The corresponding coronary angiogram demonstrated prominent septal perforators arising from the LAD artery. By exploiting the non-linear oscillation properties of microbubbles and the linear oscillation properties of tissue, at low MI, contrast-specific imaging has the ability to enhance the contrast signal while suppressing the myocardial signal. This form of contrast imaging has high temporal and spatial resolution, enabling visualization of relatively small structures in real time. Clinical relevance of this finding includes the ability to enhance coronary blood flow evaluation, which would have utility in those studies where spectral Doppler is being used to evaluate coronary blood flow and coronary flow reserve and it may be beneficial in the identification of septal perforator arteries that should be injected with alcohol during percutaneous septal ablation for the management of hypertrophic obstructive cardiomyopathy.

Traumatic cardiogenic shock due to massive air embolism. A possible role for cardiopulmonary bypass

Systemic arterial embolism is a potentially lethal complication of bronchopulmonary venous fistula in trauma patients with blunt chest trauma or isolated penetrating lung injury on positive pressure ventilation. A high index of suspicion, early diagnosis and management in specialized centres are keys to a successful outcome.