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Excerpt
The definition of ‘diastolic dysfunction’ is even more vague than that of ‘systolic dysfunction’ due to the different and relatively independent phases characterizing diastole. Does it mean prolonged relaxation? Is it referring to increasing filling pressure to achieve a given left ventricular volume in a given time (i.e. dP/dV)? Or is it purely left ventricular compliance at a given distending pressure? Some reseachers carefully avoid this spurious definition and simply name the detectable abnormalities as alterations of diastolic filling or diastolic properties of the left ventricle, which is probably a better choice. In addition to this uncertainty in the definition, the use of information derived from an examination of left ventricular diastolic filling properties in clinical practice (and in an individual patient evaluation) does not necessarily improve our decision-making and ability to identify treatment. Even in the case of clear congestive heart failure (CHF), there is doubt about the clinical utility of exploring diastolic filling because, on clinical grounds, the evidence of ‘normal’ systolic function automatically defines impaired diastolic filling [5,6]. Impaired diastolic filling is in fact a constant in every case of CHF, while systolic function is not necessarily always abnormal [7].
Moreover, whether or not medications can change some or all left ventricular diastolic characteristics independently of the clinically useful and documented effects on left ventricular mass and systolic function should be studied before proposing the evaluation of diastolic filling in hypertensive patients in clinical practice.
Based on the current evidence, extensive examination of diastolic filling characteristics does not help the clinical management of patients with arterial hypertension when information on left ventricular geometry and systolic performance has already been obtained and considered to be discriminating for classification of risk. Rather, extension of echocardiographic procedures probably aggravates the temporal, organizational and, in some circumstances, financial burden of hypertension work-up (echocardiographic information useful for hypertension can be obtained with limited studies). A balance among timing, expenses and evidence should comprise the basis of every attempt to translate indications produced by epidemiological settings or experimental designs into clinical practice. The study by Gerdts et al. [2] is very important for physiological understanding, but does not address the issue of whether filling characteristics of patients can positively change with improvement of their geometric alterations and systolic function. It is not only possible, but also very likely that regression of the gross left ventricular anatomic and functional problems in this group of patients, by aggressively correcting their hypertension (a decision that can just be based on their electrocardiogram), tracks an improvement of left ventricular filling characteristics. This might be clinically relevant.
