replace objectManger

I have a phtml file. I want to get the product short description by SKU.
I can use ObjectManager to do the work. But looks like this is not a proper way to do it.
Anyone can help with recommendation to replace ObjectManager method? Thanks!

<?= $block->getProductName($item->getProductId()) ?>
<?= $item->getProductId() ?>
<?= $item->getSku() ?>
<?php
$objectManager =  MagentoFrameworkAppObjectManager::getInstance();

   $currentproduct = $objectManager->create('MagentoCatalogModelProductRepository')->get($item->getSku());
   echo $currentproduct ->getShortDescription();
?>

rest of the code

<?php
// @codingStandardsIgnoreFile

?>
<?php $helper = $this->helper('MagentoCatalogHelperOutput'); ?>
<?php /** @var $items MagentoSalesModelOrder */ $items = $block->getOrder(); ?>
<?php if ($items): ?>
    <?php
    foreach ($items as $item) {
        $order = $item->getOrder();
    }

    ?>
    <div style="width:100%;padding:10px 0 20px 0;height:auto;min-height:360px" class="review-email-form-wrapper">
        <p><?= /* @escapeNotVerified */ __('your purchased items:') ?></p>
        <ul>
            <?php /** @var $item MagentoSalesApiDataOrderItemInterface */ ?>
            <?php foreach ($items as $item): ?>
            <?php $productUrl=$block->getProductReviewUrl($item->getProductId()) ?>
                <li>
                    <a href="<?= $escaper->escapeUrl($productUrl) ?>"><?= /* @escapeNotVerified */ $block->getProductName($item->getProductId()) ?></a>
                </li>
            <?php endforeach; ?>
        </ul>
        <p><?= /* @escapeNotVerified */ __('Thankyou for your feedback', $order->getStore()->getGroup()->getName()); ?></p>
    </div>
<?php endif; ?>