Introduction to Cardiovascular Physiology, 3Ed
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Introduction to Cardiovascular Physiology has become an essential text in its field, appealing to candidates for the FRCA, MRCP, MRCS / AFRCS, as well as medical and physiology students.
This new edition incorporates several changes and additions; in particular, there have been rapid advances made in the understanding of the active nature and roles of the endothelium, and this has resulted in the addition of a new chapter on endothelial cell biology. Many other areas have been updated, eg response of heart cells to ischaemia; role of integrins; myogenic mechanisms and the mechanisms underlying many other vascular contractile responses. New figures have been added and references updated. Finally, in reaction to the recent GMC induced changes in medical education, a problem-based element has been incorporated in the book.
attention in hot weather. Cutaneous vasodilatation also increases the local capillary filtration pressure leading to interstitial swelling: this is why a ring often feels tighter on the finger during hot weather. Measurement of human cutaneous blood flow Measurements of skin surface temperature (thermography) have been used as an index of flow but this is unreliable because skin temperature depends on ambient temperature as well as blood flow. Venous occlusion plethysmography of a digit is
(asterisk) determines the interval between heart beats. Inward currents are shown as negative values, outward currents as positive values. The ‘funny’ inward background current if produces depolarization of the pacemaker potential, and is carried by sodium ions (and some calcium ions in the late phase). The main inward current labelled iCa is due mostly to calcium ions, but can be subdivided into further currents. (After Noble, D. (1984) see Further reading list, by permission) The decay of the
sarcoplasmic reticulum are accelerated resulting in a shorter systole. The effect of noradrenaline is therefore to stimulate a more forceful and shorter systole. This has the following effects on ventricular pressure and volume. Ventricular pressure rises more rapidly in the isovolumetric phase (see Figure 6.15a) and a higher arterial pressure is produced. The maximum rate of rise of pressure, dP/dtmax, can be measured with a transducer-tipped cardiac catheter and may, with caution, be used as
(upper arm) occludes venous return and the wrist cuff eliminates hand blood flow from the measurement. The initial swelling rate (tangent to curve) measures forearm blood flow. Swelling rate tails off as venous back-pressure rises. After a few minutes (not shown here; see Figure 9.3) forearm blood volume stabilizes because venous pressure exceded cuff pressure and venous outflow resumes Kety’s tissue-clearance method This method measures microvascular blood flow in a small, local region of
hypotension (low arterial pressure). Renal tubular damage in particular is a not uncommon complication of severe hypotension. 1.8 Central control of the cardiovascular system The behaviour of the heart and blood vessels has to be regulated in order to deal with varying environmental and internal stresses. This involves nervous and neuroendocrine reflexes, which are coordinated by the brainstem and higher regions of the brain. One of the most important cardiovascular reflexes, the arterial